Drug Abuse

Question 1

Mention effect of psychoactive drugs on reward system

Answer 1

Heroin, alcohol cannabis and tobacco act om VTA to release DA into NAc causing euphoria. Alcohol causes release of endogenous opioids
BZD, stimulate DA in VTA amd inc euphoric effect of other drugs
Amphetamine and cocaine act directly on NAc nerve terminal to stimulate release and/ or inhibit reuptake to DA thus inc DA in NAc

Question 2

Describe reward deficiency and withdrawal

Answer 2

Chronic drug use causes dopaminergic neurons degeneration, leading to chronic DAS feelings and person can’t function without the drug thus craved it due to +ve and -ve reinforcement
Key element of withdrawal is corticotrphin releasing factor ane NA nurons in amydala. Heroin activity causes sympathetic overactivity, inc HR and BP

Question 3

Describe management of BZD and barbiturate dependence

Answer 3

Short acting agents are replaced by longer acting agents which have smoother withdrawal

Question 4

Describe symptoms of alcohol withdrawal

Answer 4

Delirium tremens, delirium, tremors and psychosis

Question 5

Describe management of alcohol abuse

Answer 5

1. Diazepam or chlordiazepoxide as long acting sedatives and anticonvulsants
2. Thiamine supplements
3. Psychotherapy
4. Detoxification: disulfuram (accumulates acetaldehyde leading to vomiting, nausea, flushing) + naltrexone + acamprosate (dec craving)

Question 6

Describe management of opioid abuse

Answer 6

1. Methadone or burenorphine instead of short acting agents
2. Naltrexone
3. Symptomatic: anxiolytics, antiemetics, antispasmodics, clonidine

Question 7

Describe mechanism of nicotone action

Answer 7

Stimulates a4b2 nicotinic Ach receptors in VTA, DA release in reward pathway thus reward experienced upon smoking and craving and dependence.

Question 8

Describe managemnt of nicotine abuse

Answer 8

1. Psychotherapy
2. Nictotine replacemnet
3. Bupropion
4. Vareniciline: partial agonist at nicotic Ach a4b2 receptors

Question 9

Injection of cocaine is assoxiated with…..while intranasal……

Answer 9

Intense euphoria and inc risk of infection
Less euphoria, nasal septum perforation

Question 10

Mention risks associated with LSD abuse

Answer 10

Bad trips, flashbacks, psychosis

Question 11

Describe management of LSD abuse

Answer 11

Calm the patient during bad trips
BZDs - antipsychotics

Question 12

Mention risks of chronic abuse of cannabis

Answer 12

1. Inc risk of psychosis
2. Red eyes
3. Apathy
4. Sexual and reproductive dysfunction, miscarriage and ectopic pregnancy
5. Gayeway drug
6. Immune system impaired

Question 13

Describe management of cannabis abuse

Answer 13

Naltrexone, buspirone OR fluoxetine, dronabinol

Question 14

…..are used as antiemetic in cancer chemotherapy

Answer 14

Dronabilone or nabilone