Abuse of Drugs

Question 1

Agent Factors:

Factors that influence the likelihood that a beginning drug user will lose control and develop an addiction

Answer 1

Availability of drug
Cost
Potency
Mode of administration
Speed of onset and term. of effects (pharmacokinetics)

Question 2

Host Factors:

Factors that influence the likelihood that a beginning drug user will lose control and develop an addiction

Answer 2

Genes: Innate tolerance, speed of developing acquired tolerance, likelihood of experiencing intoxication as pleasure

Metabolism of drug
Psych symp.
Prior experiences
Tendency to take risk-taking behaviour

Question 3

Environment Factors

Factors that influence the likelihood that a beginning drug user will lose control and develop an addiction

Answer 3

social setting
community attitudes
other sources of pleasure
employment/education
environmental cues

Question 4

Which two neural pathways are most affected by drugs of abuse

Answer 4

Dopamine (eg. mesolimbic pathway) and serotonin

Question 5

A student is found at a party with depressed level of consciousness preceded by euphoria

On examination :
Pupillary miosis
Conjunctival injection
Injection sites identified on arms
Decreased respiratory rate and bradycardia
Absent bowel sounds (constipation)

What drug is most likely involved?

Answer 5

Opioid

Miosis is giveaway

Question 6

What are symptoms of opioid OD

Answer 6

respiratory depression and failure
bradycardia
hypovolemia
pulmonary oedema
coma
aspiration pneumonia
rhabdomyolysis

Question 7

What are typical u-opioid receptor characteristics

Answer 7

cause euphoria, inhibit GABA neurons

Question 8

What are typical characteristics of k-opioid receptors

Answer 8

dysphoria, inhibit dopamine neurons

Question 9

What is more potent, heroin or morphine

Answer 9

Heroin (also greater availability)

Question 10

How is Heroin administered

Answer 10

IV, IM, subcut, inhaled, smoked

Question 11

What are some of the signs of Opioid withdrawal

Answer 11

Signs generally opposite of those induced by the drug

Nausea, vomiting, diarrhoea
Insomnia, myalgia (treat by giving u agonists)
Sweating, mydriasis, lacrimation, rhinorrhoea, agitation
Tachycardia, raised BP

Question 12

What is the treatment of Opioid withdrawal?

Answer 12

Naloxone
Naltrexone

Question 13

What is the difference between Naloxone and Naltrexone

Answer 13

Naloxone: Acts within minutes (life-saving). Good for acute cases of intoxication

Naltrexone: Longer duration of action, better for long-term management of opioid and alcohol dependence

Question 14

What are some of the benefits of methadone

Answer 14

substitute for suppressing heroin withdrawal syndrome as it reduces pain to tolerable level like morphine but does not produce euphoric symptoms

Question 15

A student presents to the EC, anxious with hallucinations and tachycardia

What drug was most likely taken?

Answer 15

Weed

Question 16

Cannabinoids characteristics

Answer 16

THC: long terminal half-life, euphoria and relaxation (fast-onset)

THC essentially disinhibits dopamine neurons (inhibits GABA neurons in VTA)

Question 17

Abrupt cessation symptoms of exogenous cannabinoids

Answer 17

Restlessness
Irritability
Agitation
Insomnia
Cramps

Question 18

Dependence on exogenous cannabinoids symptoms

Answer 18

Heavy daily use: panic attacks, acute psychosis, hallucinations

Question 19

How do you treat Cannabinoid severe reaction?

Answer 19

Benzo

Question 20

24 year old female attended a new years party. She had multiple alcoholic beverages to drink:
An hour later she was euphoric, elated and socially disinhibited. Later that evening experienced difficulty with balance and muscle co-ordination.

According to her friend she started behaving more erratic and vomited twice. Following that she became comatose and required intubation when the paramedics arrived.

What is the most likely drug involved

Answer 20

Alcohol

Question 21

Alcohol poisoning signs

Answer 21

Hypothermia
hypoglycaemia (especially in children)
metabolic acidosis
electrolyte disturbances
cardiac arrhythmias may also occur
aspiration of vomitus may result in pneumonitis and pulmonary oedema

Vomiting from alcohol’s disruptive effect on the semi-circular canalsof the inner ear and chemical irritation of the gastric mucosa.
Blood ethanol levels above 400 mg% (87 mmol/L) may be fatal. (The potential lethal dose of ethanol in the non-tolerant adult is 5 – 6 g/kg and 3 g/kg for children.)
Chronic ethanol abusers may survive considerably higher blood ethanol levels