Addiction

Question 1

Define Tolerance

Answer 1

Reduced responsiveness to a drug caused by previous administration.

Question 2

What are the two mechanisms of tolerance?

Answer 2

• Dispositional
  
  • Less drug reaches the active site
• Pharmacodynamic (aka tissue or functional tolerance)
  
  • Site of action is less affected by the drug

Question 3

Describe the dispositional mechanism of tolerance.

Answer 3

• less drug reaches the active site, eg
  
  • decreased rate of absorption
  • increased rate of metabolism to inactive metabolites
  • decreased rate of metabolism to active metabolites
  • increased rate of excretion

Question 4

Describe the pharmacodynamic mechanism of tolerance.

Answer 4

• site of action is less affected by the drug, eg
  
  • down-regulation or internalisation of drug receptors
  • reduced signalling down stream of drug receptors
  • some other compensatory mechanism

Question 5

What is the withdrawal phenomena?

Answer 5

The withdrawal effect of the drug is usually the opposite of the acute effect.

Question 6

Examples of stimulants.

Answer 6

• Cocaine
• Amphetamine

Question 7

Cocaine desireable effects

Answer 7

• Stimulant and euphoriant
• Increased alertness and energy
• Increased confidence and impaired judegment
• Lessens appetite and desire for sleep

Question 8

Cocaine damaging effects

Answer 8

• Damage to nose and airways
• Convulsions with respiraotry failure
• Cardiac arrhythmias and MI
• Hypertension and CVA
• Toxic confusion
• Paranoid psychosis

Question 9

Cocaine withdrawal effects

Answer 9

• Depression
• Irritability
• Agitation
• Craving
• Hyperphagia
• Hypersomnia

Question 10

Amphetamine effect

Answer 10

Similar to cocaine but longer lasting

Question 11

Examples of opiates

Answer 11

• Opium
• Morphine
• Heroin
• Methadone
• Codeine and dihydrocodeine

Question 12

Heroin is taken by:

Answer 12

• Snorting
• Smoking
• Injection

Smoking is the safest and injecting is the most dangerous method of use.

Question 13

Effects of heroin:

Answer 13

• Analgesia
• Drowsiness and sleep
• Mood change (euphoria, intense pleasure)
• Respiratory depression
• Cough reflex depression
• Sensitisationof the labyrinth with nausea and vomiting
• Decreased sympathetic outflow (bradycardia and hypotension)
• Lowering of body temperature
• Pupillary constriction
• Constipation

Question 14

Effects of heroin overdose

Answer 14

• Respiratory arrest with a pulse
• Pinpoint pupils unreactive to light
• Snoring giving way to shallow respiration
• (<8 breaths/min)
• Bradycardia and hypotension
• Varying degree of reduced conciousness/coma

Question 15

Side effects of opiates

Answer 15

• First time
  
  • nausea/vomiting
  • headache
• Medium term -
  
  • phlebitis
  • anorexia
  • constipation
• Longer term
  
  • tolerance
  • withdrawal
  • social and health problems

Question 16

Opiate withdrawal syndrome

Answer 16

• Craving
• Insomnia
• Yawning
• Muscle pain and cramps
• Increased salviary, nasal and lacrimal secretions
• Dilated pupils
• Piloerection

Question 17

Benefits of methadone maintainance

Answer 17

• Decriminalises drug use
• Allows normalisation of lifestyle
• Reduces IV misuse

Question 18

Ecstasy (MDMA) - Effects

Answer 18

• Euphria followed by a feeling of calm
• Increased sociability
• Inability to distingush between what is and isn’t desireable
• Effects after 20 minutes lasting 2-4 hours

Question 19

Ecstasy (MDMA) - side effects

Answer 19

• Nausea and dry mouth
• Increased blood pressure and temperature
• Large doses can cause anxiety and panic
• Drug induced psychosis

Question 20

What is the psychoactive agent in cannabis?

Answer 20

Tetrahydrocannabinol (THC)

Question 21

Psychological effects of cannabis

Answer 21

• Relaxing or stimulating
• Euphoriant
• Increases sociability and hilarity
• Increases appetite
• Changes in time perception
• Synaesthesia

Question 22

Psychological effects of higher doses of cannabis.

Answer 22

• Anxiety
• Panic
• Persecutory ideation
• Hallucinatory activity

Question 23

Cannabis - side effects

Answer 23

• Respiratory problems as with tobaco
• Toxic confusion
• Exacerbation of major mental illness

Question 24

Physical side effects of steroids

Answer 24

• Skin - acne, stretch marks, baldness
• Feminisation in males with hypogonadism and gynaecomastia
• Virilisation in women including hirsutism, deep voice, clitoral enlargement, menstrual irregularities, hair thinning
• Cardiovascular - increased cholesterol and hypertension
• Growth deficits due to premature closure of epiphyses
• Liver disease - cholestatic jaundice, liver tumours

Question 25

Pschological side effects of steroids

Answer 25

• Irritability and anger - roid rage
• Hypomania and mania
• Depression and suicidality on withdrawal