Case 3 - Drug Misuse

Question 1

What are the symptoms of alcohol withdrawal?

Answer 1

Symptoms start at 6-12 hours:

• Headache
• Tremor
• Nausea
• Sweating
• Tachycardia
• Anxiety
• Breathing difficulties

Seizure peak incidence at 36 hrs

Peak incidence of delirium tremens at 48-72 hrs - this can last as long as 5 days and has high mortality:

• Coarse tremor
• Tachycardia and HTN
• Fever
• Insomnia
• Confusion
• Fluctuating motor activity (from hyperexcitabiltiy to lethargy)
• Delusions
• Auditory / visual hallucinations

Question 2

What is the mechanism of alcohol withdrawal?

Answer 2

chronic alcohol consumption enhances GABA mediated inhibition in the CNS (similar to benzodiazepines) and inhibits NMDA-type glutamate receptors

alcohol withdrawal is thought to be lead to the opposite (decreased inhibitory GABA and increased NMDA glutamate transmission)

Question 3

What medications are 1st line for alcohol withdrawal?

Answer 3

1st line = benzodiazepines e.g. chlordiazepoxide

• Lorazepam - may be preferrable in hepatic failure
• Carbamazepine - also effective in withdrawal

Anticonvulsant
- Uses: 1st line for partial seizures, neuropathic pain, bipolar disorder

Question 4

What condition can be caused by thiamine deficiency and who is this condition most commonly seen in?

Answer 4

Wernicke’s encephalopathy

Commonly seen in alcoholics
Triad:
- Opthalmoplegia / nystagmus
- Ataxia
- Confusion

Investigations:

• ↓ red cell transketolase (↓ by thiamine deficiency)
• MRI

Treatment:
- Thiamine replacement e.g. straight thiamine or Pabrinex (injection containing vitamin C and B i.e. thiamine)

Complications:
- If not treated, pt may develop Korsakoff syndrome as well

Question 5

What is Korsakoff syndrome?

Answer 5

Neuropsychiatric condition often caused by failure to treat Wernicke’s encephalopathy

Associated with:

• Wernicke’s encaphalopathy triad: ophthalmoplegia / nystagmus, ataxia and confusion
• Anterograde + retrograde amnesia - immediate memory intact, but short-term is diminished
• Confabulations

Question 6

What are the criteria for dependence syndrome?

e.g. alcohol

Answer 6

ICD-10 criteria

Require:
[3 of the following either …
- ​present together at some point during the previous year OR
- constantly for 1 month]

• Strong craving / compulsion to take substance
• Lost control of substance use - difficulty controlling substance-taking behaviour in terms of its onset, termination, or levels of use
• Tolerance
• Physiological withdrawal state when substance is stopped/reduced
• Neglect of other pleasures/interests because of substance use,↑ time for obtaining, taking or recovering from substance
• Persistant use of substance despite evidence of harmful effects

Another characteristic feature (not part of ICD-10) is narrowing of repertoire i.e. tendency to use the same substance, in the same way, on weekdays and weekends, regardless of social constraints.

Question 7

What medication might be given to deter a patient from drinking alcohol?

Answer 7

Disulfiram

• Produces an acute sensitivity to alcohol i.e. symptoms of hangover are felt immediately with only a small amount of alcohol
• MoA: inhibits acetaldehyde dehydrogenase enzyme

Question 8

Name 2 drugs which might be given to reduce alcohol craving?

Answer 8

Acamprosate and Naltrexone

• Naltrexone can also be used for opioid dependence

Question 9

Which of the following medications is used to treat acute mania in bipolar disorder?

• Methylphenidate
• Lithium
• Olanzapine
• Sertraline
• Lorazepam

Answer 9

Olanzapine

• Methylphenidate (ritalin is a form of this) - used for ADHD
• Lithium - used in mood stabilisation and prophylaxis of mania, depression, bipolar, self-harming behaviour
• Sertraline - anti-depressant thus not recommended for mania
• Lorazepam - sedates patient but doesn’t treat mania

Question 10

What medications are contraindicated when taking Lithium?

• Olanzapine
• Sodium valproate
• Paracetamol
• Naproxen
• Chlordiazepoxide

Answer 10

Naxproxen

lithium is renally excreted and NSAIDs can ↓ renal function

Question 11

What tool can be used to gauge alcohol withdrawal severity + guide therapy?

Answer 11

CIWA-Ar

(Clinical Institute Withdrawal Assessment for Alcohol, revised)

10 questions
Score (max = 67):
- ≤8 = absent or minimal withdrawal
- 9-19 = mild to moderate withdrawal
- ≥20 = severe withdrawal

Benzodiazepines - used to control psychomotor agitation + prevent progression to more severe withdrawal

• Chlordiazepoxide (Librium)
• Lorazepam (Ativan)
• Diazepam (Valium)