CNS Drugs Flashcards
Amphetamines
Ritalin
Indicated for: Narcolepsy, weight control, and ADHD
MOA: Stimulates all areas of the brain by increasing the release of norepinephrine and dopamine in the brain. Sympato-mimetic. Responses include increased alertness, wakefulness, decreased fatigue, mood elevation/euphoria, increased initiative, and decreased appetite
May cause: Nervousness, anxiety, sleeplessness, increased HR, increased BP, arrhythmias, sleeplessness and excessive crying and growth suppression in children, and possible bone marrow suppression
Contraindicated for: Insomnia/psychological disorders, hypertension, cardiac arrhythmias, and anorexia.
Drug interactions: Anticholinergics, anticoagulants, anticonvulsants, and tricyclic antidepressants
POTENTIAL FOR ABUSE
Xanthines
Caffeine, Theobromine, Theophylline/Aminophylline
Indicated for: Pain from headache, asthma, bronchitis, emphysema, and drowsiness (Minimal therapeutic usefulness)
MOA: Increases CNS activity by inhibiting breakdown of cyclic AMP. Responses include CNS stimulation, cardiac stimulation, blood vessel constriction in the brain, diuresis, and bronchiorelaxation
May cause: Increased HR, cardiac arrhythmia, increased gastric secretions (esp. caffeine), diuresis, excess CNS stimulation (convulsions, insomnia), and headache and irritability upon withdrawal
Contraindicated for: Cardiac arrhythmia, ulcers, and excessive consumption during pregnancy
ACTIVATE CP450 ENZYMES, POSSIBLE DRUG INTERACTIONS
Cocaine
Lidocaine, Benzocaine
Indicated for: Local anesthetic (ONLY FDA-approved use)
MOA: Stimulates all areas of the brain by increasing the release of norepniephrine and dopamine in the brain. Local effects not understood.
May cause: Initially anxiety, restlessness, confusion, dizziness, tremors, convulsions, then later depression, unconsciousness, bradycardia, hypotension, cardiac arrest, and possible death. Allergic reactions not common, but possible
Contraindicated for: Any use other than as a local anesthetic
Barbiturates
Phenobarbital
Indicated for: Situational and neurotic anxiety, sedation, anti-convulsant, sleep disorders, and general anesthesia
MOA: Possible inhibition of the reticular activating system. GABA independent.
May cause: Drowsiness, impared performance, decreased perception, impaired judgment, hyperalgesia, respiratory depression, and a hangover effect with serious withdrawal symptoms possible when discontinued
Contraindicated for: Taking with other sedative-hypnotics, tendency for drug abuse, and pregnancy.
May be taken orally
Speed and duration of action depend upon different kinds available
ACTIVATE CP450 ENZYMES, POSSIBLE DRUG INTERACTIONS
NO ANALGESIA, CAUSES HYPERALGESIA
Benzodiazepines
Diazepam
Indicated for: Situational and neurotic anxiety, sedation, anti-convulsant, sleep disorders, and general anesthesia
MOA: Binds to a special receptor to decrease brain activity and also increase GABA activity. GABA-dependent.
May cause: Drowsiness, impaired performance, decreased perception, impaired judgment, anterograde amnesia, respiratory depression, and possible hangover effect with severe withdrawal symptoms when discontinued
Contraindicated for: Taking with other sedative-hypnotics, tendency for drug abuse, and pregnancy.
Overdose may be reversed by competitive antagonist flumazenil
ACTIVATE CP450 ENZYMES, POSSIBLE DRUG INTERACTIONS
NO ANALGESIA
Ethyl alcohol
Indicated for: None
MOA: Increase in GABA activity during short-term use. Long-term use sees decrease of depressive effects.
May cause: Drowsiness, impaired performance, decreased perception, impaired judgment, cerebellar atrophy, respiratory depression, and possible hangover effect with severe withdrawal symptoms when discontinued
Contraindicated for: Head trauma, taking with other sedative-hypnotics, tendency for drug abuse, and pregnancy.
ACTIVATE CP450 ENZYMES, POSSIBLE DRUG INTERACTIONS
Goals of Anesthesia
1) Analgesia
2) Amnesia and loss of consciousness
3) Muscle relaxation
Inhalation Anesthetics
Isoflurane, Nitrous Oxide
CNA depressants
Responses: Loss of consciousness, amnesia
May cause: Respiratory depression, lowered blood pressure, decreased heart rate, arrhythmia, malignant hypothermia, and post-operative nausea and vomiting
Nitrous oxide acts as an adjunct only
Thiopental (Barbiturate)
Intravenous anesthetic
Causes loss of consciousness, hyperalgesia
May cause: Respiratory depression, lowered blood pressure, decreased heart rate, malignant hypothermia, and post-operative nausea and vomiting
NO ARRHYTHMIA
IV administration works in seconds, is eliminated quickly
Ketamine
NOT a CNS depressant
NO RESPIRATORY DEPRESSION, NO SKELETAL MUSCLE RELAXATION
May cause: Increased respiration, increased heart rate, analgesia without loss of consciousness at low dose, loss of consciousness at higher dose, and nightmares and hallucinations upon regaining consciousness
Antiepilectic Agents/Anticonvulsant Drugs
Indicated for: Seizures
MOA: Decreased CNS excitability by changing electrolyte movement or changing neurotransmitter (increase GABA, decrease glutamate)
Adverse effects: Sedation, kidney damage, liver damage, blood diseases
Levodopa
Indicated for: Parkinsonism
MOA: Moves more dopamine into the brain, increasing its availability
May cause: Jerking movements, drooling, anorexia, nausea, vomiting, palpitations, arrhythmias, blood pressure changes, orthostatic hypertension, aggravation of narrow-angle glaucoma, and compulsive behavior
Used in combination with carbidopa
Must be discontinued slowly
Anticholinergic drugs
Indicated for: Parkinsonism
MOA: Blocks muscarinic receptors in brain, decreases acetylcholine receptivity of brain
May cause: Confusion, insomnia
Must be discontinued slowly
Carbidopa
Indicated for: Parkinsonism
MOA: Prevents conversion of levodopa to dopamine peripherally, but not centrally
Decreases side effects of levodopa when used in conjuction
Narcotics
Opioids
Indicated for: Pain relief without loss of consciousness, cough suppression (antitussive), and chronic/acute diarrhea
MOA: Blocks mu and kappa receptors in the CNS to decrease the release of substance p and inhibit excitatory transmissions from nerve terminals carrying painful stimuli
May cause: Stimulation of the brain’s emetic center, respiratory depression, constipation, restlessness, excitement, tremors, delirium, insomnia, and physical dependence
Contraindicated for: Respiratory depression/emphysema and head injuries
Withdrawal symptoms: Chills, hot flashes, tearing, runny nose, sneezing, drowsiness, anxiety, twitching, cramps, vomiting, diarrhea, diluted pupils, elevated body temperature, increased heart rate, and increased blood pressure
TENDENCY FOR TOLERANCE, ABUSE, AND PHYSICAL DEPENDENCE