Drug:
Substance P |
| Mechanism of Action: Substance P is
a undecapeptide, is abundant both in the periphery and in the CNS, where
it is usually co-localised with one of the classical neurotransmitters,
most commonly serotonin (5-HT). A role for Substance P is proposed in the
regulation of pain, asthma, psoriasis, inflammatory bowel disease and, in
the CNS, emesis, migraine, schizophrenia, depression and anxiety. |
| Major drug Interactions: clinical
studies demonstrated that treatment with the Substance P (NK1 receptor)
antagonist aprepitant (also known as MK-0869) significantly improves
depression symptoms and reduces the incidence of chemotherapy-induced nausea
and vomiting. |
Drug:
Monoamines |
| Description: In the brain monoamines
are serotonin and the catecholamines (norepinephrine,
dopamine & some epinephrine).The monoaminergic neurons
comprise less than 1% of all neurons in the CNS, yet still play very important
functions. They belong to the non-hierarchical, long axon system (once source,
multiple targets). Some neurons can have 50,000 nerve endings. |
| Mechanism of Action: All receptors
are metabotropic (except for 5HT-3) and belong to the
same receptor superfamily. The receptors are typically G-protein
coupled and when stimulated affect Ca or K channels and/or a protein kinase
pathway. Because of the homology between receptors for the different neurotransmitters,
there is considerable crossover pharmacology, with drugs acting "primarily"
on one neurotransmitter receptor also commonly producing "side effects"
mediated by actions on the other receptor subtypes within this superfamily
(i.e. there is a lack of drug selectivity because of the similar structure/sequence
of the different receptor subtypes). Example: Antipsychotics are dopamine
antagonists, but also effect norepi & serotonin receptors. |
| Major drug Interactions: All stored
monoamine neurotransmitters can be released via indirectly acting amines
(e.g. amphetamine), cocaine blocks the reuptake of all monoamines, and reserpine
can decrease the entry of all of them into presynaptic storage vesicles. |
| Drug: Ethanol |
| Drug Class: CNS Depressant |
| Mechanism of Action: There isn’t
a specific “ethanol” receptor. CNS effects result from effects
on a variety of membrane proteins involved in neurotransmission, including
an enhancement of GABA at GABA-A receptors & inhibition of glutamate
in opening NMDA receptor/channels. |
| Symptoms of poisoning: unable to walk
in a normal manner, listing from side to side, slurred speech, slowed breathing,
vomiting, stupor, coma. Chronic ethanol abuse is the leading cause of liver
cirrhosis & the need for liver transplantation in the US. Ethanol oxidation
produces an increased NADH/NAD ratio & excess acetaldehyde. |
| Pharmacokinetics: Peak blood levels
are achieved within 30 mins after oral ingestion. Presence of food delays
absorption by slowing gastric emptying. Vd is similar to total body water
content. Over 90% of ethanol is oxidized in the liver, with the remainder
excreted through the lungs & the urine. The rate of metabolism is dose-dependent,
but at levels usually achieved in the blood, the rate of oxidation follows
zero-order kinetics (i.e. is independent of time & concentration). A
typical adult can metabolize 7-10g (150-220 mmol) of ethanol per hour (the
equivalent of 10oz of beer, 3.5 oz of wine or 1oz of 80 proof spirits). |
| Major drug interactions: chronic
ethanol consumption can induce
cyt P450; this can increase the hepatotoxicity of acetaminophen
due to increased conversion to reactive hepatotoxic metabolites. Acute
alcohol use may inhibit the metabolism of other drugs due
to decreased metabolism &/or decreased liver blood flow (such as tricyclic
antidepressants, phenothiazines & sedative-hypnotic drugs). Pharmacodynamic
interactions may also occur with other drugs including CNS depressants |
Notes: Ethanol consumption can
result in alcohol tolerance (to some degree) and both psychological and
physical dependence |
| Reference: medline
|
| Drug: Methanol
(methyl alcohol, wood alcohol) |
| Class: industrial solvent
found in many commercial solvents including “canned heat” and
windshield-washing fluid. |
| Mechanism of Action: methanol &
its metabolites are much more potent toxins than ethanol. |
| Indications: None |
| Side Effects: blurred
vision with relatively clear sensorium that may take up
to 30 hours to develop after absorption. Formaldehyde may be detectible
on the breath. Bradycardia, retinal damage,
prolonged coma, seizures, respiratory depression,
metabolic acidosis with an elevated anion gap &
osmolar gap. A decrease in serum bicarbonate. |
| Pharmacokinetics: methanol can be
absorbed through the skin, respiratory or GI tracts. It is oxidized to form
formaldehyde, formic acid & a reactive species of carbon dioxide. |
Notes: Three specific modalities
of treatment for severe methanol poisoning: 1) suppression of metabolism
by alcohol dehydrogenase to toxic products by giving ethanol i.v.; 2)
hemodialysis; 3) treatment of the acidosis with bicarbonate. |
| Drug: Isopropyl
alcohol (rubbing alcohol) |
| Indications: found in rubbing alcohol
& alcohol swabs |
| Side Effects: unresponsive reflexes,
low urine output, uncoordinated movements, slowed breathing, nausea/vomiting,
low blood pressure, dizziness, stupor, coma |
| Notes: Call poison control immediately,
take container with you to the emergency room. Recovery depends on amount
ingested, amount of time before treatment, and occurence of kidney damage.
Ingestion of isopropyl alcohol is potentially fatal. Treatment includes
administering activated charcoal, using gastric lavage, treating breathing
difficulties, maintaining blood pressure & dialysis. |
| Drug: Levodopa
(l-dopa) (Dopar ®, Larodopa ®) |
| Drug Class: treatment of Parkinson's Disease |
| Mechanism of Action: The symptoms
of Parkinson's disease is related to depletion of striatal dopamine. Levodopa
is the metabolic precursor of dopamine and (unlike dopamine) it can cross
the blood-brain barrier where it is presumably decarboxylated to dopamine
in the basal ganglia. |
| Indications: Parkinson's disease |
| Contraindications: narrow angle glaucoma,
undiagnosed skin lesions or history of melanoma (which may be activated
by levodopa) |
| Side Effects:Involuntary choreiform
and/or dystonic movements, anorexia, nausea , paranoid ideation, depression |
Pharmacokinetics: Taken orally;
it's absorption depends on the rate of gastric emptying & gastric
pH. Food delays it's absorption. Plasma half life 1-3 hrs. Only 1-3% of
administered levodopa makes it into the CNS if given alone due to peripheral
decarboxylation to dopamine, which is doesn't cross the BBB. It is therefore
commonly given with a dopa decarboxylase inhibitor (carbidopa) that does
not cross the BBB. This reduces the daily requirement for levodopa by
~75%. |
| Major drug Interactions: MAOIs (must
be discontinued for at least 2 weeks prior to levodopa therapy), phenothiazines,
butyrophenones, phenytoin, antihypertensive drugs (postural hypotension)
|
| Notes: loses effectiveness within
a few years |
| Reference: www.rxlist.com |
| Drug: Carbidopa
(Lodosyn ®) |
| Drug Class: treatment of Parkinson's
Disease |
| Mechanism of Action: an
inhibitor of aromatic amino acid decarboxylation. Carbidopa
reduces peripheral dopamine formation and thus peripheral peripheral side
effects of levodopa when given concomitantly (see Katzung). |
| Indications: Parkinson's disease |
| Contraindications: see levodopa |
| Side Effects: see levodopa |
| Pharmacokinetics: Oral tablets, capsules
(also comes combined with levodopa) |
| Major drug Interactions: see levodopa |
| Notes: see levodopa |
| Reference: www.rxlist.com |
| Drug: Levodopa
+ carbidopa (Sinemet ® ) |
| Drug Class: Antiparkinsonism |
| Mechanism of Action: Levodopa
is converted to dopamine
by aromatic acid decarboxylase. Carbidopa is an inhibitor of aromatic amino
acid decarboxylation. |
| Indications: Parkinson's disease |
| Contraindications: patients with a
history of melanoma |
| Side Effects: see levodopa |
| Pharmacokinetics: Oral tablets, capsules
|
| Major drug Interactions: see levodopa |
| Notes: see levodopa |
| Drug: Bromocriptine
(Parlodel ®) |
| Drug Class: Dopamine (D2) agonist |
| Mechanism of Action: an ergot derivative
that selectively stimulates D2 dopamine receptors. Unlike levodopa, dopamine
agonists do not require enzymatic conversion to an active metabolite, have
no potentially toxic metabolites, and do not compete with other substances
for active transport into the blood and across the blood/brain barrier.
|
| Indications: a
drug of first choice in
treating Parkinson's disease
& certain endocrinologic disorders, especially hyperprolactemia. Dopamine
agonists may be combined with levodopa &/or carbidopa in treating Parkinson's
disease. |
| Contraindications: history of psychotic
illness, recent myocardial infarction or peptic ulceration. It should also
be avoided in patients with peripheral vascular disease. |
| Side Effects: Selective D2 agonists
can have more limited adverse effects compared to levodopa. They have a
lower incidence of response fluctuations & dyskinesias that occur with
long-term levodopa therapy. |
| Reference: Katzung's text |
| Drug: Selegiline
or deprenyl (generic,
Eldepryl ®) |
| Drug Class: Selective MAO-B inhibitor |
| Mechanism of Action: retards
the breakdown of dopamine. As a result it can prolong the
anti-Parkinsonism effect of levodopa, and allow a reduction in the dose
of levodopa needed. |
| Indications: as an adjunct
therapy for patients with a declining or fluctuating response
to levodopa. Selegiline has only a minor therapeutic effect on Parkinsonism
when given alone, but may decrease disease progression, perhaps due to its
antioxidant action (reduced generation of free radicals), or an antiapoptotic
mechanism produced by its metabolite (desmethylselegiline). |
| Contraindications: patients taking
meperidine, tricyclic antidepressants, or SSRIs because of the risk of toxic
reactions (serotonin syndrome). |
| Notes: MAO-B is the primary isoform
of MAO that dopamine is metabolized by. MAO-A metabolizes norepinephrine
& serotonin. |
| Reference: Katzung's text |
| Drug: Benztropine
(Cogentin ®) |
| Drug Class: Antimuscarinic |
| Mechanism of Action: similar to atropine |
| Indications: may improve
the tremor & rigidity of parkinsonism, but has no effect
on bradykinesia. |
| Contraindications: patients with prostatic
hyperplasia, obstructive GI disease or angle-closure glaucoma. |
| Side Effects: drowsiness, mental slowness,
inattention, confusion, delusions, hallucinations, mood changes. Dryness
of the mouth, blurred vision etc. (remember "mad
as a hatter, red as a beet, ...."). |
| Reference: Katzung's text |
| Drug: Baclofen
(Lioresal ®) |
| Drug Class: skeletal muscle relaxant (spasmolytic) |
| Mechanism of Action: A GABA-B
receptor agonist. Activation of receptors increases K conductance
(hyperpolarization) that produces a presynaptic inhibitory effect to reduce
the release of excitatory neurotransmitters by decreasing Ca influx. Baclofen
is a structural analog of GABA and it's chemical name is p-chlorophenyl-GABA.
|
| Clinical Indications: Alleviation
of severe spasticity resulting from multiple
sclerosis & in patients with spinal
chord injuries. |
| Contraindications: may cause hypotension
& dyspnea when used with epidural morphine. |
| Side Effects: drowsiness, dissiness,
weakness |
| Pharmacokinetics: When injected intrathecally,
effective CSF concentrations can be achieved with resultant plasma concentrations
100 times less than with oral administration. Can be taken orally. |
| Major drug Interactions: |
Notes: WARNING:
Abrupt discontinuation of intrathecal baclofen, regardless of the cause,
has resulted in sequelae that include high fever, altered mental status,
exaggerated rebound spasticity, and muscle rigidity, that in rare cases
has advanced to rhabdomyolysis, multiple organ-system failure and death. |
| Reference: www.rxlist.com |
| Drug: Diazepam
(Valium ®) |
| Drug Class: benzodiazepine |
| Mechanism of Action: act
on parts of the limbic system, the thalamus
and hypothalamus, and induces
calming effects. |
| Clinical Indications: Management of
anxiety disorders; relief of agitation & tremor in acute alcohol withdrawal;
adjunct prior to endoscopic procedures to reduce apprehension; relief
of skeletal muscle spasm due
to reflex spasm caused by local
pathology (inflammation or trauma)
or upper motor neuron disorders (e.g. cerebral
palsy), tetanus. |
| Contraindications: glaucoma,drug hypersensitivity,
hypersenstivity to soy protein (contained in the injectible emulsion dosage
form) |
| Side Effects: fatigue, drowsiness,
ataxia, confusion |
| Pharmacokinetics: Can be given i.v.,
i.m., orally |
| Major drug Interactions: no information |
| Notes: Diazepam is a controlled substance
listed in Schedule IV. Withdrawal symptoms may occur with sudden discontinuation. |
| Reference:
www.rxlist.com |
| Drug: Dantrolene
(Dantrium ®) |
| Drug Class: skeletal muscle relaxant (spasmolytic) |
| Mechanism of Action: produces skeletal
muscle relaxation by interfering with the
release of calcium from the sarcoplasmic reticulum through the SR calcium
channel complex. Establishes a more normal level of ionized
intracellular calcium when given after a triggered hyperthermic reaction
has occured (which elevates intracellular calcium levels). |
| Clinical Indications: used immediately
for treatment of fulminant hypermetabolism of skeletal muscle characteristic
of malignant hyperthermia;
it is also indicated pre- and post-operatively to decrease the development
of malignant hyperthermia in patients judged to be susceptible to this reaction |
| Side Effects: loss of grip strength
& leg weakness, subjective CNS complaints (in normal patients); |
| Pharmacokinetics: given i.v. (push)
in response to onset of symptoms of malignant hyperthermia; the dose required
to cause symptorms to subside may vary; can also be given orally prior to
surgery. Dantrolene is metabolized by hepatic microsomal enzymes |
| Major drug Interactions: may potentiate
vencuronium-induced NMJ block |
| Notes: Use of 100% oxygen and supportive
measures are also used in treating malignant hyperthermia (which has a ~50%
death rate if not treated with dantrolene) |
| Reference: www.rxllist.com |
| Drug: Cyclobenzaprine
(Flexeril ®) |
| Drug Class: relieves skeletal muscle spasm
of local origin |
| Mechanism of Action: Not
totally clear (has pharmacological similarities to tricyclic
antidepressants). It acts within the CNS &
brain stem to reduce tonic somatic motor activity. Potentiates
norepinephrine, and has potent central and peripheral anticholinergic effects;
antagonizes reserpine |
| Clinical Indications: an adjunct to
rest and physical therapy for short term relief
of muscle spasm associated with acute, painful musculoskeletal
conditions; use for longer than 2 weeks is not warranted |
| Contraindications: MAOIs (within 2
weeks), recovery from acute MI, patients with a history of cardiac arrhythmias,
hyperthyroidism |
| Side Effects: sedation, dry mouth,
dizziness |
| Pharmacokinetics: large intersubject
variability in plasma levels, half life 1-3 days |
| Major drug Interactions: May enhance
the effects of other CNS depressants (alcohol, barbiturates). |
| Reference: www.rxlist.com |
| Drug: Morphine
(generic) |
| Drug Class: narcotic analgesic |
| Mechanism of Action: opioid mu-receptor
agonist |
| Indications: pain relief |
| Contraindications: drug hypersensitivity |
| Side Effects: constipation,
nausea, vomiting, dizziness, sedation, respiratory depression, circulatory
depression, apnea, shock |
| Pharmacokinetics: PO, Transdermal,
Rectal. Metabolized in the liver, 2-4 hr half life |
| Major drug Interactions: other CNS
depressants |
| Notes: can cause psychological
& physical dependence |
| Reference: www.rxlist.com |
| Drug: Codeine
(generic) |
| Drug Class: narcotic analgesic |
| Mechanism of Action: opioid agonist.
The major effects of codeine are on the central nervous system and the bowel.
|
| Clinical Indications: For the relief
of mild to moderate pain |
| Contraindications: Hypersensitivity
to codeine |
| Side Effects: lightheadedness, dizziness,
sedation, nausea, vomiting, and sweating, dry mouth, constipation. Serious
overdose will cause respiratory depression. |
| Pharmacokinetics: Oral tablets. Codeine
is readily absorbed from the gastrointestinal tract with the maximum analgesic
effect occurring 60 minutes post administration. Codeine retains at least
one half its analgesic activity when administered orally. Dosage should
be adjusted according to the severity of the pain and the response of the
patient. |
| Major drug Interactions: |
| Notes: DEA order form
required for prescriptions |
| Reference: www.rxlist.com |
Drug: Dextromethorphan |
| Drug Class: nonnarcotic antitussive |
| Mechanism of Action: Selectively
depresses the cough center in the medulla. Dextromethorphan
15-30 mg is equal to 8-15 mg codeine as an antitussive. |
| Clinical Indications: symptomatic
relief of nonproductive cough due to colds or inhaled irritants. |
| Contraindications: persistent or chronic
cough or when cough is accompanied by excessive secretions. Use during first
trimester of pregnancy unless directed otherwise by physician. Use in children
less than 2 years of age. |
| Side Effects: CNS: Dizziness, drowsiness.
GI: N&V, stomach pain. |
| Pharmacokinetics: Does not produce
physical dependence or respiratory depression. Well absorbed from GI tract.
Onset: 15-30 min. Duration: 3-6 hr. |
| Major drug Interactions: use with
MAO inhibitors may cause nausea, hypotension, hyperpyrexia, myoclonic leg
jerks, and coma. |
| Reference: http://www.healthdigest.org/drugs/ |
| Drug: Hydrocodone
(when combined w/ acetaminophen = Vicodin
®) |
| Drug Class: a semisynthetic narcotic analgesic
and antitussive |
| Mechanism of Action: opioid agonist
with multiple actions qualitatively similar to those of codeine |
| Clinical Indications: Relief of moderate
to moderately severe pain |
| Contraindications: hypersensitivity
to opiates. Use with caution, if at all, in clients
with head injuries as the CSF pressure may be increased
further. |
| Side Effects: lightheadedness, dizziness,
sedation, nausea, and vomiting |
| Major drug Interactions: additive
effects with other CNS depressants such as narcotic analgesics, antipsychotics,
antianxiety agents, alcohol. The concurrent use of anticholinergics with
hydrocodone may produce paralytic ileus. |
| Notes: A schedule III drug |
| Reference: www.rxlist.com |
| Drug: Oxycodone
(when combined with aspirin =
Percodan ®) |
| Drug Class: narcotic analgesic (semisynthetic) |
| Mechanism of Action: a semi-synthetic
narcotic with multiple actions qualitatively similar to those of morphine
|
| Clinical Indications: relief of moderate
to severe pain, including that due to cancer, injuries, arthritis, lower
back problems, and other musculoskeletal conditions that require treatment
for more than a few days. Produces mild sedation with little anti-tussive
effect. |
| Contraindications: hypersensitivity
to opiates, hypercarbia, paralytic ileus, children or during labor |
| Side Effects: light headedness, dizziness,
sedation, nausea and vomiting |
| Pharmacokinetics: PO. Onset: 15-30
min. Peak effect: 60 min. Duration: 4-6 hr. half-life: 3.2 hr for immediate-release
product and 4.5 hr for extended-release. |
| Major drug Interactions: additive
effects with other CNS depressants |
| Notes: indicated only
for opiate-tolerant clients.
|
| Reference: www.rxlist.com |
| Drug:Tramadol |
| Drug Class: A centrally acting analgesic not
related chemically to opiates. |
| Mechanism of Action: Precise mechanism
is not known. It may bind to mu-opioid receptors and inhibit reuptake of
norepinephrine and serotonin. The analgesic
effect is only partially antagonized by the antagonist naloxone.
|
| Clinical Indications: Management of
moderate to moderately severe pain |
| Contraindications: Hypersensitivity
to tramadol. In acute intoxication with alcohol, hypnotics, centrally acting
analgesics, opiates, or psychotropic drugs |
| Side Effects: Dizziness, vertigo,
headache, somnolence, CNS stimulation, anxiety, confusion, seizures. |
| Pharmacokinetics: Rapidly absorbed
after PO administration. Food does not affect the rate or extent of absorption.
Onset: 1 hr. Peak effect: 2-3 hr. Peak plasma levels: 2 hr. Plasma half-life:
Approximately 7 hr after multiple doses. Extensively metabolized by one
of the P-450 isoenzymes. Excreted in the urine, with about 30% excreted
unchanged and 60% as metabolites. |
| Major drug Interactions: alcohol &
other CNS depressants, increased risk of seizures
if naloxone is used to treat tramadol overdose. |
| Notes: Causes significantly less respiratory
depression than morphine. In contrast to morphine, tramadol does not cause
release of histamine. |
| Reference: www.rxlist.com |
| Drug: Meperidine
(Demerol ®) |
| Drug Class: Narcotic analgesic (synthetic) |
| Mechanism of Action: opiate agonist |
| Clinical Indications: Analgesic for
moderate to severe pain. Particularly useful for minor surgery, as in orthopedics,
ophthalmology, rhinology, laryngology, and dentistry; also for diagnostic
procedures such as cystoscopy, retrograde pyelography, and gastroscopy |
| Contraindications: Hypersensitivity
to drug, convulsive states as in epilepsy, tetanus and strychnine poisoning,
children under 6 months, diabetic acidosis, head injuries, shock, liver
disease, respiratory depression, increased cranial pressure, and before
labor during pregnancy. Use with caution in lactation. |
| Side Effects: Transient hallucinations,
transient hypotension (high doses), visual disturbances. |
| Pharmacokinetics: Oral, IM or IV administration.
Meperidine is significantly less effective by the oral than by the parenteral
route. Duration is less than most opiates. Oral onset: 10-45 min. Peak effect:
30-60 min. Duration: 2-4 hr. half-life: 3-4 hr. |
| Major drug Interactions: tricyclics
(additive anticholinergic effects) |
| Notes: One-tenth
as potent an analgesic as morphine. Its analgesic effect
is only one-half when given PO rather than parenterally. Has no
antitussive effects and does
not produce miosis. Less smooth muscle spasm, constipation,
and antitussive effect than equianalgesic doses of morphine. Produces both
psychologic and physical dependence; overdosage causes severe respiratory
depression. The narcotic antagonist, naloxone
hydrochloride, is a specific antidote against respiratory depression
which may result from overdosage or unusual sensitivity to narcotics. |
| Reference: www.rxlist.com |
| Drug: Methadone |
| Drug Class: Narcotic analgesic, morphine type
(synthetic) |
| Mechanism of Action: a synthetic narcotic
analgesic with multiple actions quantitatively similar to morphine |
| Clinical Indications: Severe pain.
Detoxification and maintenance of narcotic
dependence. |
| Contraindications: IV use, liver disease,
during pregnancy, in children, or in obstetrics (due to long duration of
action and chance of respiratory depression in the neonate). Use with caution
during lactation. |
| Side Effects: Marked constipation,
excessive sweating, pulmonary edema, choreic movements. |
| Pharmacokinetics: Oral or IV administration.
Oral onset: 30-60 min. Peak effects: 30-60 min. Duration: 4-6 hr. Half-life:
15-30 hr. Both the duration and half-life increase with repeated use due
to cumulative effects. |
| Major drug Interactions: |
| Notes: Produces
only mild euphoria, which is the reason it is used as a
heroin withdrawal substitute and for maintenance programs. Produces physical
dependence; withdrawal symptoms develop more slowly and are less intense
but more prolonged than those associated with morphine. Does not produce
sedation or narcosis. |
| Reference: www.rxlist.com |
| Drug: Buprenorphine
(Buprenex ®) |
| Drug Class: Narcotic analgesic, morphine type
(synthetic) |
| Mechanism of Action: Buprenex is a
parenteral opioid analgesic with 0.3 mg Buprenex being approximately equivalent
to 10 mg morphine sulfate in analgesic and respiratory depressant effects
in adults. |
| Clinical Indications: for the relief
of moderate to severe pain |
| Contraindications: IV use, liver disease,
during pregnancy, in children, or in obstetrics (due to long duration of
action and chance of respiratory depression in the neonate). Use with caution
during lactation. |
| Side Effects: sedation, nausea, dizziness |
| Pharmacokinetics: elimination half-lives
ranging from 1.2-7.2 hours (mean 2.2 hours) after intravenous administration.
Buprenorphine, in common with morphine and other phenolic opioid analgesics,
is metabolized by the liver and its clearance is related to hepatic blood
flow. |
| Major drug Interactions: |
| Notes: NALOXONE
MAY NOT BE EFFECTIVE IN REVERSING THE RESPIRATORY DEPRESSION
PRODUCED BY BUPRENEX. |
| Reference: www.rxlist.com |
| Drug: Naloxone
(Narcan ®) |
| Drug Class: a narcotic antagonist |
| Mechanism of Action: Combines competitively
with opiate receptors and blocks or reverses the action of narcotic analgesics
|
| Clinical Indications: Respiratory
depression induced by natural and synthetic narcotics, including
butorphanol, methadone, nalbuphine, pentazocine,
and propoxyphene. Drug of choice when nature of depressant
drug is not known. Diagnosis of acute opiate overdosage. Not effective when
respiratory depression is induced by hypnotics, sedatives, or anesthetics
and other nonnarcotic CNS depressants |
| Contraindications: Sensitivity to
drug. Narcotic addicts (drug may cause severe withdrawal symptoms). Use
in neonates. |
| Side Effects: N&V, sweating, hypertension,
tremors, sweating due to reversal of narcotic depression. If excessive doses
are used postoperatively - can cause ventricular tachycardia/fibrillation. |
| Pharmacokinetics: IV, IM, SC administration.
Onset: IV, 2 min; SC, IM: <5 min. Time to peak effect: 5-15 min. Duration:
Dependent on dose and route of administration but may be as short as 45
min. half-life: 60-100 min. Metabolized in the liver to inactive products;
eliminated through the kidneys. |
| Major drug Interactions: |
| Reference: www.rxlist.com |
| Drug: Naltrexone
(Trexan, Revia ®) |
| Drug Class: a narcotic antagonist |
| Mechanism of Action: Combines competitively
with opiate receptors and blocks or reverses the action of narcotic analgesics
|
| Clinical Indications: In the treatment
of alcohol dependence and
for the blockade of the effects of exogenously administered opioids.
|
| Contraindications: Sensitivity to
drug. Narcotic addicts (drug may cause severe withdrawal symptoms). Use
in neonates. Contraindicated in acute hepatitis or liver failure. |
| Side Effects: has the capacity to
cause hepatocellular injury when given in excessive doses. |
| Pharmacokinetics: 50 mg of Revia will
block the pharmacologic effects of 25 mg of intravenously administered heroin
for periods as long as 24 hours. Other data suggest that doubling the dose
of Revia provides blockade for 48 hours, and tripling the dose of Revia
provides blockade for about 72 hours. |
| Notes: has a longer
duration of action compared to naloxone & therefore
more appropriate drug for long-term treatment
of addiction to heroin or other opioids. |
| Reference: www.rxlist.com |
| Drug: Meperidine
(Demerol ®) |
| Drug Class: Narcotic analgesic (synthetic) |
| Mechanism of Action: opiate agonist
(w/ significant antimuscarinic effects) |
| Clinical Indications: Analgesic
for moderate to severe pain. Particularly useful for minor
surgery, as in orthopedics, ophthalmology, rhinology, laryngology, and dentistry;
also for diagnostic procedures such as cystoscopy, retrograde pyelography,
and gastroscopy |
| Contraindications: Hypersensitivity
to drug, convulsive states as in epilepsy, tetanus and strychnine poisoning,
children under 6 months, diabetic acidosis, head injuries, shock, liver
disease, respiratory depression, increased cranial pressure, and before
labor during pregnancy. Use with caution in lactation. |
| Side Effects: Transient hallucinations,
transient hypotension (high doses), visual disturbances. There is a potential
for producing seizures in patients receiving high doses, or patients with
renal compromise due to the accumulation of a metabolite (normeperidine). |
| Pharmacokinetics: Oral, IM or IV administration.
Meperidine is significantly less effective by the oral than by the parenteral
route. Duration is less than most opiates. Oral onset: 10-45 min. Peak effect:
30-60 min. Duration: 2-4 hr. half-life: 3-4 hr. |
| Major drug Interactions: tricyclics
(additive anticholinergic effects) |
| Notes: One-tenth as potent an analgesic
as morphine. Its analgesic effect is only one-half when given PO rather
than parenterally. Has no antitussive effects and does not produce miosis.
Less smooth muscle spasm, constipation, and antitussive effect than equianalgesic
doses of morphine. Produces both psychologic and physical dependence; overdosage
causes severe respiratory depression. The narcotic antagonist, naloxone
hydrochloride, is a specific antidote against respiratory depression which
may result from overdosage or unusual sensitivity to narcotics. |
| Reference: www.rxlist.com |
| Drug: Morphine
(generic) |
| Drug Class: narcotic analgesic |
| Mechanism of Action: opioid mu-receptor
agonist |
| Indications: pain relief |
| Contraindications: drug hypersensitivity |
| Side Effects: constipation, nausea,
vomiting, dizziness, sedation, respiratory depression, circulatory depression,
apnea, shock |
| Pharmacokinetics: PO, Transdermal,
Rectal. Metabolized in the liver, 2-4 hr half life |
| Major drug Interactions: other CNS
depressants |
| Notes: can cause psychological &
physical dependence |
| Reference: www.rxlist.com |
| Drug: Fentanyl
(Sublimaze, Duragesic ®) |
| Drug Class: Narcotic analgesic, morphine type
|
| Mechanism of Action: an opioid mu-receptor
agonist |
| Clinical Indications: Preanesthetic
medication, induction, and maintenance of anesthesia of short duration and
immediate postoperative period. Restricted
use for the management of severe chronic pain that cannot be managed with
less powerful drugs |
| Contraindications: Not used for acute
or postoperative pain (including out-patient surgeries). The transmucosal
form is contraindicated in children who weigh less than 10 kg, for the treatment
of acute or chronic pain (safety for this use not established). Use outside
the hospital setting is contraindicated. Myasthenia gravis and other conditions
in which muscle relaxants should not be used. Clients particularly sensitive
to respiratory depression. Use during labor. Lactation. |
| Side Effects: Skeletal and thoracic
muscle rigidity, especially after rapid IV administration. Bradycardia,
seizures diaphoresis. Transmucosal form may cause life-threatening hypoventilation.
|
| Pharmacokinetics: IM, IV, Transdermal,
Transmucosal (Oral Lozenge) routes of administration. For IV use - onset:
7-8 min. Peak effect: Approximately 30 min. Duration: 1-2 hr. Half-life:
1.5-6 hr. |
| Major drug Interactions: |
| Notes: Duragesic ® (fentanyl transdermal
system) is a transdermal system providing continuous systemic delivery of
fentanyl for 72 hours. |
| Reference: www.rxlist.com |
| Drug Class: inhalational General Anesthetics
(as a class) |
| Mechanism of Action: evidence suggests
that general anesthetics may activate GABA-A
receptors & depress spontaneous and evoked activity
of neurons in many regions of the brain |
| Clinical Indications: to produce loss
of consciousness before and during surgery |
| Contraindications: history of malignant
hyperthermia |
| Side Effects: shivering, blurred vision,hetpatotoxicity/hepatitis
(rare); malignant hyperthermia (rare but potentially fatal) |
| Pharmacokinetics: given by inhalation;
medium rate of onset & recovery from anesthesia |
| Major drug Interactions: do not drink
alcoholic beverages or take other CNS depressants (medicines that slow down
the nervous system, possibly causing drowsiness) for about 24 hours after
you have received a general anesthetic. |
| Notes: general anesthetics may cause
you to feel drowsy, tired, or weak for up to a few days after they have
been given. They may also cause problems with coordination and your ability
to think |
| Reference: www.nlm.nih.gov/medlineplus/druginfo |
| Drug: Thiopental
Sodium (Pentothal ®) |
| Drug Class: Ultra-short acting barbiturate
anesthetic |
| Mechanism of Action: binds
to components of the GABA-A receptor to increase the inhibitory effects
of GABA & depress the actions of other excitatory neurotransmitters;
induces hypnosis and anesthesia, but not analgesia |
| Clinical Indications: (1) the sole
anesthetic agent for brief (15 minute) procedures, (2) for induction of
anesthesia prior to administration of other anesthetic agents, (3) to supplement
regional anesthesia, (4) to provide hypnosis during balanced anesthesia
with other agents for analgesia or muscle relaxation, (5) for the control
of convulsive states during or following inhalation anesthesia, local anesthesia,
or other causes, (6) in neurosurgical patients with increased intracranial
pressure, if adequate ventilation is provided, and (7) for narcoanalysis
and narcosynthesis in psychiatric disorders. |
| Contraindications: absence of suitable
veins for IV administration; hypersensitivity to barbiturates, acute intermittent
porphyria |
| Side Effects: (overdose related) severe
hypotension, respiratory depression (may require intubation) |
| Pharmacokinetics: it produces hypnosis
within 30 to 40 seconds of intravenous injection. Recovery after a small
dose is rapid, with some somnolence and retrograde amnesia. Repeated
intravenous doses lead to prolonged anesthesia because fatty tissues act
as a reservoir; they accumulate Pentothal in concentrations
6 to 12 times greater than the plasma concentration, and then release the
drug slowly to cause prolonged anesthesia. The half-life of the elimination
phase after a single intravenous dose is three to eight hours. |
| Major drug Interactions: probenecid
can prolong the action of thiopental |
| Notes: WARNING: may be habit forming |
| Reference: www.rxlist.com |
| Drug: Methohexital
(Brevital ®) |
| Drug Class: rapid, ultrashort-acting barbiturate
anesthetic |
| Mechanism of Action: binds to components
of the GABA-A receptor to increase the inhibitory effects of GABA &
depress the actions of other excitatory neurotransmitters; induces hypnosis
and anesthesia, but not analgesia |
| Clinical Indications: 1.
For intravenous induction of anesthesia prior to the use of other general
anesthetic agents. 2. For intravenous induction of anesthesia
and as an adjunct to subpotent inhalational anesthetic agents (such as nitrous
oxide in oxygen) for short surgical procedures; Brevital Sodium may be given
by infusion or intermittent injection. 3. For use along
with other parenteral agents, usually narcotic analgesics, to supplement
subpotent inhalational anesthetic agents (such as nitrous oxide in oxygen)
for longer surgical procedures. 4. As intravenous anesthesia
for short surgical, diagnostic, or therapeutic procedures associated with
minimal painful stimuli (see WARNINGS). 5. As an agent
for inducing a hypnotic state. |
| Contraindications: latent or manifest
porphyria, or in patients
with a known hypersensitivity to barbiturates |
| Side Effects: ciruculatory depression,
thrombophlebitis, respiratory depression, twitching, emergence delirium,
anxiety, emesis, abdominal pain. The onset of toxicity following an i.v.
overdose will occur within seconds of the infusion. |
| Pharmacokinetics: compared to thiopental,
methohexital's duration of action is only about half as long. The drug does
not appear to concentrate in fat depots to the extent that other barbiturate
anesthetics do. Thus, cumulative effects are fewer and recovery is more
rapid with methohexital than with thiobarbiturates. |
| Major drug Interactions: chronic administration
of barbiturates or phenytoin reduces the effectiveness of methohexital.
Barbiturates may influence the absorption of other concomitantly used drugs. |
| Notes: a Schedule IV drug & may
be habit forming |
| Reference: www.rxlist.com |
| Drug: Midazolam
(generic, Versed ®) |
| Drug Class: benzodiazepine sedative; adjunct
to general anesthesia |
| Mechanism of Action: short-acting
benzodiazepine with sedative-general anesthetic properties. |
| Clinical Indications: IV or IM - preoperative
sedation, anxiolysis, and amnesia. IV: Sedation, anxiolysis, and amnesia
prior to or during short diagnostic, therapeutic, or endoscopic procedures
(either alone or with other CNS depressants). Induction of general anesthesia
before administration of other anesthetics. PO: In children to help alleviate
anxiety before a diagnostic or therapeutic procedure or before anesthesia
induction. Also to reduce ability to recall events that occurred during
sedation |
| Contraindications: hypersensitivity
to benzodiazepines. Acute narrow-angle glaucoma. Use in obstetrics, coma,
shock, or acute alcohol intoxication where VS are depressed. IA injection. |
| Side Effects: fluctuations in VS,
including decreased respiratory rate and tidal volume, apnea, variations
in BP and pulse rate are common |
| Pharmacokinetics: onset, IM: 15 min;
IV: 2-2.5 min for induction (if combined with a preanesthetic narcotic,
induction is about 1.5 min). |
| Reference: www.healthdigest.com/drugs |
Drug: Ondansetron |
| Drug Class: antiemetic |
| Mechanism of Action: a 5-HT3
(serotonin receptor subtype) antagonist |
| Clinical Indications: prevention
of nausea and vomiting associated with surgery & cancer
chemotherapy |
| Contraindications: use with caution
during lactation |
| Side Effects: diarrhea, clonic-tonic
seizures, anaphylaxis, bronchospasm, shock. |
| Pharmacokinetics: IM, IV or Oral administration.
Plasma half life 3-6 hr depending on age & route of administration.
|
| Major drug Interactions: rifampin
decreases ondansetron plasma levels & increases it's liver metabolism. |
| Notes: cytotoxic chemotherapy is thought
to release serotonin from enterochromoffin cells of the small intestine.
The released serotonin may stimulate the vagal afferent nerves through the
5-HT3 receptors, thus stimulating the vomiting reflex. |
| Reference: www.rxlist.com |
Drug: Ketorolac |
| Drug Class: NSAID |
| Mechanism of Action: possesses anti-inflammatory,
analgesic, and antipyretic effects. |
| Clinical Indications: short-term
(up to 5 days) management of severe, acute pain that requires
analgesia at the opiate level. |
| Contraindications: hypersensitivity
to the drug, angioedema & bronchospasm due to aspirin or NSAIDs; advanced
renal impairment or at risk for renal failure; patients with suspected cardiovascular
bleeding |
| Side Effects: GI bleeding & perforation,
bonchospasm, anaphylaxis |
| Pharmacokinetics: always initiate
therapy with IV or IM followed by PO only as continuation treatment, if
necessary. |
| Major drug Interactions: ketorolac
may increase plasma salicylate levels due to decreased plasma protein binding |
| Notes: use with caution in patients
with impaired hepatic or renal function, or on high-dose salicylate regimens |
| Reference: www.rxlist.com |
| Drug: Etomidate
(Amidate
®) |
| Drug Class: general anesthetic and adjunct
to general anesthesia |
| Mechanism of Action: a hypnotic
with no analgesic activity. Appears to act
like GABA and is thought to exert its mechanism by depressing
the activity of the brain stem reticular system. Minimal
CV and respiratory depressant effects. |
| Clinical Indications: induction of
general anesthesia. As a supplement to nitrous oxide during short surgical
procedures. |
| Contraindications: use with caution
during lactation. |
| Side Effects: skeletal muscle movements,
laryngospasm |
| Pharmacokinetics: IV only. Onset of
action: 1 min. Duration: 3-5 min. Plasma half life: 75 min. Rapidly metabolized
in the liver with inactive metabolites excreted mainly through the urine
|
| Reference: www.healthdigest.org/drugs |
| Drug: Propofol
(Diprivan ®) |
| Drug Class: intravenous sedative-hypnotic agent |
| Mechanism of Action: general anesthetic |
| Clinical Indications: intravenous
sedative-hypnotic agent for use in the induction
and maintenance of anesthesia or sedation. As with other
rapidly acting intravenous anesthetic agents, the half-time of the blood-brain
equilibration is approximately 1 to 3 minutes, and this accounts for the
rapid induction of anesthesia. Recovery is more rapid than with i.v. barbiturates.
Patients are able to ambulate sooner & patients “feel better”
in the post-op period compared to other i.v. anesthetics. Has
antiemetic actions, as vomiting is uncommon. |
| Contraindications: propofol should
not be used in children in intensive care units. |
| Side Effects: apnea, decreased cardiac
output, hypotension |
| Pharmacokinetics: elimination half
life is 30-60 minutes. Rapidly metabolized by the liver; conjugated to glucuronide
& sulfate and excreted |
| Notes: a popular
drug |
| Reference: www.rxlist.com |
| Drug: Remifentanil
(Ultiva ®) |
| Drug Class: narcotic analgesic |
| Mechanism of Action: mu-opioid
receptor agonist. |
| Clinical Indications: as an analgesic
during the induction and maintenance of general
anesthesia and as an analgesic
during postoperative care. |
| Contraindications: epidural or intrathecal
use because of the presence of glycine in the formulation. Hypersensitivity
to fentanyl analogues. Use with caution in obese clients and during lactation. |
| Side Effects: nausea & vomiting,
hypotension, shivering, muscle rigidity, respiratory depression |
| Pharmacokinetics: rapidly metabolized
by nonspecific blood and tissue esterases; Onset: 1 min. Peak effect: 1
min. plasma half life: 3-10 min. Recovery: Within 5-10 min. |
| Major drug Interactions: remifentanil
is synergistic with other anesthetics |
| Reference: www.rxlist.com |
| Drug: Fentanyl
(generic, Sublimaze, Duragesic ®) |
| Drug Class: narcotic analgesic, morphine type
|
| Mechanism of Action: mu-opioid
receptor agonist. |
| Clinical Indications: preanesthetic
medication, induction, and maintenance
of anesthesia of short duration and immediate postoperative
period. Supplement in general or regional anesthesia. Severe pain associated
with cancer treatment in those tolerant to opiates and experience breakthrough
pain. |
| Contraindications: use outside the
hospital setting is contraindicated. Myasthenia gravis and other conditions
in which muscle relaxants should not be used. Clients particularly sensitive
to respiratory depression. Use during labor. Lactation. |
| Side Effects: Skeletal and thoracic
muscle rigidity |
| Pharmacokinetics: IV. Onset: 7-8 min.
Peak effect: Approximately 30 min. Duration: 1-2 hr. t1/2: 1.5-6 hr. When
the oral lozenge (transmucosal administration) is sucked, fentanyl citrate
is absorbed through the mucosal tissues of the mouth and GI tract. Peak
effect, transmucosal: 20-30 min. Actiq resembles a lollipop; sucking provides
a rapid onset of action. Faster-acting and shorter duration than morphine
or meperidine. |
| Major drug Interactions: |
| Reference: www.rxlist.com;
www.healthdigest.org/drugs |
| Drug: Diazepam
(Valium®) |
| Drug Class: benzodiazepine |
| Mechanism of Action: act on parts
of the limbic system, the thalamus and hypothalamus, and induces calming
effects. |
| Clinical Indications: Management of
anziety disorders; relief of agitation & tremor in acute alcohol withdrawal;
adjunct prior to endoscopic procedures to
reduce apprehension; relief of skeletal muscle spasm due
to reflex spasm caused by local pathology (inflammation or trauma) or upper
motor neuron disorders (e.g. cerebral palsy), tetanus. |
| Contraindications: glaucoma,drug hypersensitivity,
hypersenstivity to soy protein (contained in the injectible emulsion dosage
form) |
| Side Effects: fatigue, drowsiness,
ataxia, confusion |
| Pharmacokinetics: Can be given i.v.,
i.m., orally |
| Major drug Interactions: no information |
| Notes: Diazepam is a controlled substance
listed in Schedule IV. Withdrawal symptoms may occur with sudden discontinuation. |
| Reference:
www.rxlist.com |
| Drug: Morphine
(generic) |
| Drug Class: narcotic analgesic |
| Mechanism of Action: opioid mu-receptor
agonist |
| Indications: pain relief |
| Contraindications: drug hypersensitivity |
| Side Effects: constipation, nausea,
vomiting, dizziness, sedation, respiratory depression, circulatory depression,
apnea, shock |
| Pharmacokinetics: PO, Transdermal,
Rectal. Metabolized in the liver, 2-4 hr half life |
| Major drug Interactions: other CNS
depressants |
| Notes: can cause psychological &
physical dependence |
| Reference: www.rxlist.com |
| Drug: Lidocaine
(Xylocaine ®) |
| Drug Class: local anesthetic
(amide), class 1b antiarrhythmic |
| Mechanism of Action: blocks voltage
sensitive sodium channels in nerves and cardiac tissue. |
| Clinical Indications: production of
local or regional anesthesia; treatment of ventricular cardiac arrhythmias
(esp. post- MI) |
| Contraindications: patients with history
of hypersenstivity to amide local anesthetics |
| Side Effects: (related to overdose)
lightheadedness, tinnitus, metalic taste, blured vision, numbness, twitching,
convulsions, hypotension |
| Pharmacokinetics: hepatic metabolism,
half life 1.5-2 hrs. Patients with CHF or hepatic disease will have higher
plasma levels. |
| Major drug Interactions: MAOIs or
ergot alkaloids (when using epinephrine containing solutions). Phenothiazines
may reduce the pressor effects of epinephrine |
| Notes: lidocaine is also packaged
in combination with epinephrine for local anesthetic use to prolong the
duration of local anesthesia |
| Reference: www.rxlist.com |
| Drug: Bupivacaine
(Sensorcaine ®) |
| Drug Class: local anesthetic
(amide) |
| Mechanism of Action: blocks voltage
sensitive sodium channels |
| Clinical Indications: production of
local or regional anesthesia |
| Contraindications: patients with history
of hypersenstivity to amide local anesthetics |
| Side Effects: (related to overdose)
lightheadedness, tinnitus, metalic taste, blured vision, numbness, twitching,
convulsions, hypotension, cardiac arrhythmias |
| Pharmacokinetics: longer
duration of action than most other local anesthetics (e.g.
vs. lidocaine) & 16 times more potent
than lidocaine; plasma half life is 2.7 hrs (adults), 8 hrs (neonates).
|
| Major drug Interactions: MAOIs or
ergot alkaloids (when using epinephrine containing solutions). Phenothiazines
may reduce the pressor effects of epinephrine |
| Notes: also packaged in combination
with epinephrine for local anesthetic use to prolong the duration of local
anesthesia |
| Reference: www.rxlist.com |
| Drug: Mepivacaine
(Carbocaine ®) |
| Drug Class: local anesthetic
(amide) |
| Mechanism of Action: blocks voltage
sensitive sodium channels |
| Clinical Indications: production of
local or regional anesthesia |
| Contraindications: patients with history
of hypersenstivity to amide local anesthetics |
| Side Effects: (related to overdose)
lightheadedness, tinnitus, metalic taste, blured vision, numbness, twitching,
convulsions, hypotension |
| Pharmacokinetics: medium
duration of action (similar to lidocaine) & twice
as potent as lidocaine |
| Major drug Interactions: none |
| Reference: www.rxlist.com |
| Drug: Ropivacaine
(Naropin ® ) |
| Drug Class: local anesthetic
(amide) |
| Mechanism of Action: blocks voltage
sensitive sodium channels |
| Clinical Indications: production of
local or regional anesthesia |
| Contraindications: patients with history
of hypersenstivity to amide local anesthetics |
| Side Effects: (related to overdose)
lightheadedness, tinnitus, metalic taste, blured vision, numbness, twitching,
convulsions, hypotension |
| Pharmacokinetics: long
duration of action (similar to bupivacaine) & 16
times as potent as lidocaine |
| Major drug Interactions: none |
| Reference: www.rxlist.com |
| Drug: Tetracaine
(Pontocaine ®) |
| Drug Class: Local anesthetic
(ester) |
| Mechanism of Action: blocks voltage
sensitive sodium channels |
| Clinical Indications: production of
local or regional anesthesia |
| Contraindications: patients with history
of hypersenstivity to ester local anesthetics |
| Side Effects: (related to overdose)
lightheadedness, tinnitus, metalic taste, blured vision, numbness, twitching,
convulsions, hypotension |
| Pharmacokinetics: Long
duration of action (similar to bupivacaine) & 16
times as potent as lidocaine |
| Major drug Interactions: none |
| Reference: Katzung's text |
| Drug: 2-chloroprocaine
(Nesacaine ®) |
| Drug Class: Local anesthetic
(ester) |
| Mechanism of Action: blocks voltage
sensitive sodium channels |
| Clinical Indications: production of
local or regional anesthesia |
| Contraindications: patients with history
of hypersenstivity to ester local anesthetics |
| Side Effects: (related to overdose)
lightheadedness, tinnitus, metalic taste, blured vision, numbness, twitching,
convulsions, hypotension |
| Pharmacokinetics: Rapid
onset & short duration
of action. Reduced acute toxicity due
to rapid metabolism (plasma half life ~25 seconds). |
| Major drug Interactions: none |
| Reference: www.rxlist.com |
| Drug: Procaine
(Novocain ®) |
| Drug Class: Local anesthetic
(ester) |
| Mechanism of Action: blocks voltage
sensitive sodium channels |
| Clinical Indications: production of
local or regional anesthesia |
| Contraindications: patients with history
of hypersenstivity to ester local anesthetics |
| Side Effects: (related to overdose)
lightheadedness, tinnitus, metalic taste, blured vision, numbness, twitching,
convulsions, hypotension |
| Pharmacokinetics: Short
duration of action (relative to lidocaine) & similar
potency as lidocaine |
| Major drug Interactions: none |
| Reference: Katzung's text |
| Drug: Triptans,
eg. Sumatriptan (Imitrex ®) |
| Drug Class: Treatment of migraines, Selective
Serotonin (5-HT-1 subtype) agonists |
| Mechanism of Action: Serotonin
(5-HT1) agonist. Activation of 5HT1B or 5-HT1D receptors
inhibits the activation of the trigeminal nerve and this effect inhibits
meningeal vasodilation. By this mechanism these drugs produce
meningeal vasoconstriction. |
| Clinical Indications: Acute treatment
of migraine and variant migraine headaches. Effective for cluster headaches
as well. |
| Contraindications: Ischemic
cardiac, cerebrovascular, or peripheral vascular disease. Note:
Triptan-type drugs produce vasoconstriction, and (like the ergot alkaloids)
must therefore be used with care in ischemic heart disease, pregnancy, Reynaud’s
disease & other peripheral vascular diseases. If there are risk factors
for coronary artery disease, a stress test is indicated prior to prescribing
these drugs. |
| Side Effects: Coronary
artery vasospasm, hypertensive episodes |
| Pharmacokinetics: IM or PO, metabolized
by monoamine oxidase, 2.5 hr halflife |
| Major drug Interactions: Do not give
to patient on MAO inhibitor |
| Notes: Significant first-pass hepatic
metabolism when given orally. |
| Reference: www.rxlist.com |
| Drug: Beta Blockers,
e.g. Propranalol (Inderal ®) or Timolol
(Blocadren ®) |
| Drug Class: Beta adrenergic receptor blockers |
| Mechanism of Action: Non-selective
beta blockers. Beta blockers decrease the frequency & severity of attacks.
They block beta receptors in the locus coeruleus,
which produces an unopposed alpha-receptor response. This may be a mechanism
of migraine prevention. Propranolol may also block some serotonin (5-HT2)
receptors in the brain. The clinical relevance of this effect is unclear. |
| Clinical Indications: Migraine
prevention (prophylaxis). Of no value in the treatment of
acute migraine. (For other indications see beta blocker section / ANS &
Cardiac drugs) |
| Contraindications:Cardiogenic shock,
sinus bradycardia and greater than first degree block, bronchial asthma,
CHF unless the failure is secondary to a tachyarrhythmia treatable with
propranalol. |
| Side Effects: Sinus bradycardia, AV
block, hypotension, CHF. Fatigue, depression, impotence, decreased libido.
May precipitate bronchospasm. |
| Reference: www.rxlist.com |
