Substance Abuse 2 Flashcards
Examples of Hallucinogenic agents (one big one to know)
Big one: LSD (Lysergic acid diethylamide)
Others: ergot alkaloids, peyote/mescaline, mushrooms/psilocybin, dimethyltryptamine, bufotenine
Duration and potency of LSD
Long duration (up to 12h), very potent (.5-3ug/kg)
Effects of LSD on you
Effects: hallucinations, dizziness, mydriasis, tremor, blurred vision, altered awareness of shape & color, micropsia (things seem small),macropsia (things seem large), mood swings, detachment. You will know you’re hallucinating.
Mechanism of LSD
Mechanism: partial agonist at 5-HT2 receptors (serotonin receptors)
How bad is the compulsion/addictive potential of LSD?
No addiction/physical dependence, very little compulsive use, little cross-tolerance to other hallucinogens, but tolerance to other drugs w/ similar mechanism
PCP and ketamine are examples of what types of drugs?
Dissociative drugs
Alternate names for PCP (2)
(phencyclidine, Angel Dust)
Mechanism of PCP
Mechanism: non-competitive Glu NMDA R antagonists; act as channel blockers to dec Ca2+ conductance
There are both acute AND chronic effects of PCP.
What are the initial acute effects?
Acute effects: intoxication, blank stare, muscular rigidity, analgesia, hypersalivation, sweating, hypertensive crisis, bizarre, aggressive behavior, paranoid delusions/psychoses, convulsions
There are both acute AND chronic effects of PCP.
What are the chronic effects?
Chronic effects: difficulty in organized thinking, memory deficits, speech impairment
How do we treat PCP? How about the specific effects of it?
Tx acute sx: avoid stimuli (dark quiet room),
convulsions – diazepam,
htn – hydralazine,
psychoses – haloperidol
Withdrawal symptoms of PCP
Withdrawal: depression, anxiety, irritability, restlessness, anergia, sleep disturbances
What other substance in high doses causes similar effects as PCP?
a/w: dextromethorphan in cough syrup can produce similar effects at high doses
Ketamine is also known as:
date rape drug (Rohypnol is what is commonly referred to as the date rape drug (blocks new memory formation), but keep this link in mind in case it comes up on the faculty exam)
Effect of Ketamine
effect: hallucinations, loss of consciousness
Ethanol is metabolized how?
Metabolism: EtOH –(OH dehydrogenase)–> acetaldehyde –(aldehyde DH)–> acetic acid (taken up in Krebs cycle) *pathway requires NAD+
How do we excrete ethanol?
10% excreted unaltered in sweat, breath, urine. Rest metabolized mainly in liver. Minor pathway: CYP2E1
Dual mechanistic action of ethanol
inhibition of glutamate-activated cation currents at NMDA-R → dec neuronal excitability
potentiation of GABA-A R activated chloride currents → facilitates GABA-induced hyperpolarization, dec excitability (aka general CNS depression)
What does ethanol do to the liver?
Effects on liver: inc NADH/NAD+ ratio→ inc FA synthesis, dec FA oxidation; inc plasma FFA, dec release of TAG from liver→accumulation of TAG (labs: inc GGT, AST 2x > ALT)
What does ethanol due in the periphery?
Peripheral effects: inc gastric acid secretion, inc sympathetic tone & epi release → vasodil, heat loss, arrhythmias, inhib ADH secretion → diuresis
Central effects of ethanol
Central effects: euphoria, inc reaction time, impaired judgment, loss of emotional control, impaired gait, ataxia, loss of balance, slurred speech, analgesia, confusion, sedation
Higher order: emesis, coma, death from respiratory depression
What happens to chronic ethanol drinkers AND WHY?
Chronic effects: tolerance - metabolic(inc CYP2E1), pharmacodynamic (dec effects on NMDA, GABA R’s), physical dependence & addiction.
Fatty liver, alcoholic hepatitis, cirrhosis→ portal htn and hepatocellular carcinoma.
Other cancers: oral, larynx and esophagus.