Drug Abuse

Question 1

ethanol, nicotine site of action

Answer 1

actions at the level of VTA (ventral tegmental area)

- increase dopamine release

Question 2

cocaine, amphetamines, cannabinoids site of action

Answer 2

actions at the level of nucleus accumbens

- increase dopamine release

Question 3

opioids site of action

Answer 3

actions affecting both ventral tegmental area and nucleus accumbens
- increase dopamine release

Question 4

opioid detox

Answer 4

methadone

Question 5

alcohol or sedative hypnotics

Answer 5

benzodiazepines

Question 6

smoking cessation

Answer 6

transdermal nicotine patches or varenicline

Question 7

clonidine

Answer 7

reduce sx of SNS overactivity during opiate withdrawal

Question 8

benzos

Answer 8

reduce anxiety associated with withdrawal from diverse drugs

Question 9

varenicline or bupropion

Answer 9

reduce relapses during smoking cessation

Question 10

disulfiram therapy

Answer 10

aversive conditioning for alcoholics

- evoke physical distress due to acetaldehyde poisoning

Question 11

naltrexone therapy

Answer 11

opioid addicts or alcohlics treatment

- opioid receptor antagonist reduces rewarding effects of drugs

Question 12

acamprostate therapy

Answer 12

alcoholics

- mild NMDA receptor antagonism reduces reinforcing effects of drug abuse

Question 13

methadone maintenance

Answer 13

harm reduction

• reduces craving for heroin and induces tolerance that impairs rewarding effect of heroin
• less criminal activity and incarceration
• improves health, employment, education and family/social outcomes

Question 14

amphetamine, methamphetamine, cocaine, methylphenidate

Answer 14

stimulant
- evoke release of catecholamines in periphery and CNS
- CNS effects due to blockade of dopamine reuptake
Sx: sympathomimetic toxidrome (increased HR, increased RR, hyperthermia, mydriasis, euphoria, increased speech
OD: anxiety, agitation, paranoia, seizures, arrhythmias, MI, cerebral hemorrhage, rhabdomyolysis

Question 15

MDMA

Answer 15

similar to amphetamines but release 5HT and produce mild hallucinogenic effects

Question 16

LSD and mescaline

Answer 16

5HT2A partial agonists
Sx: hallucinations, increased HR, increased RR, mydriasis, nausea, altered perceptions
OD: not lifethreatening

Question 17

phencyclidine, ketamine

Answer 17

NMDA receptor antagonist
Sx: euphoria, hallucinations, agitation/violent behavior, psychosis, catatonia, anxiety/panic, increased HR, increased BP, increased RR, miosis, nystagmus, rhabdomyolysis
OD: coma, seizures, renal failure, death

Question 18

cannabinoids

Answer 18

Tx: anorexia due to AIDS, prevent N/V
Sx: euphoria, conjunctivitis, ptosis, increased HR, appetite

Question 19

rimonobant

Answer 19

CB1 antagonist, developed to treat obesity to reduce appetite, withdrawn from market due to concern about psych adverse effects depression

Question 20

fomepizole

Answer 20

CAD inhibitor
Tx: methanol or ethylene glycol poisoning
- blocks formation of toxic metabolites

Question 21

Ethanol

Answer 21

Effects: CNS impaired, CV depression, alters liver metabolism, inflammation and erosive gastritis with chronic use, ethanol inhibits ADH release, increases desire but decreases physiological responses and performance

Pharm: metabolized by CAD (rate limiting) and MEOS and mitochondrial acetaldehyde dehydrogenase

Drug interactions: induces P450 metabolism of same drugs

Mech: GABAa receptor function enhanced, NMDA glutamate receptor function

Uses: nerve lysis, treatment of methanol or ethylene glycol poisoning

Tolderance and dependence
Withdrawal gives delirium tremens which is lifethreatening, anxiety, seizures, hallucinations

peripheral neuropathy, wernike’s encephalopathy

fetal alcohol syndrome –> craniofacial abnormalities, microcephaly, mental retardation