Psychiatric Shit

Question 1

1. Regarding lithium

• a. It is responsible for inducing type II diabetes
• b. It requires no treatment in overdose
• c. It is metabolised by first pass effects in the liver
• d. Dosing does not need to be reduced in renal impairment
• e. It is excreted almost entirely in the urine

Answer 1

e. It is excreted almost entirely in the urine

Question 2

2. Haloperidol

• a. Is more sedative than chlorpromazine
• b. May lower the convulsive threshold
• c. Is a potent dopamine agonist
• d. Has potent anti-cholinergic effects
• e. Has a low incidence of extra-pyramidal reactions

Answer 2

b. May lower the convulsive threshold

• a. Is less sedative than chlorpromazine
  
  • Low sedation, chlorpro is medium, olanzapine high
• c. Is a potent dopamine antagonist
• d. Has ??? anti-cholinergic effects
• e. Has a high incidence of extra-pyramidal reactions
  
  • Primary ADR for haloperidol

Question 3

3. Regarding chlorpromazine which is NOT true?

• a. It is more than 80% protein bound
• b. Is has a plasma half life of approximately 6 hours
• c. It is excreted in urine and faeces
• d. It induces hepatic microsomal enzymes
• e. Plasma levels are increased by concomitant administration of anticholinergic anti-parkinsonian agents

Answer 3

d. It induces hepatic microsomal enzymes

Question 4

4. Haloperidol

• a. Can cause significant nausea
• b. Has low extrapyramidal toxicity
• c. Has a high clinical potency
• d. Acts primarily at GABA receptors
• e. Belongs to the thienobenzodiazepam drug family

Answer 4

c. Has a high clinical potency

• a. Is an antiemetic
• b. Has high extrapyramidal toxicity
• d. Acts primarily at Dopamine (D2) receptors
• e. Belongs to the butyrophenone drug family
  
  • Olanzapine is a thienobenzodiazepam

Question 5

5. The drug used as an antipsychotic most likely to cause extrapyramidal effects is

• a. Chlorpromazine
• b. Lorazepam
• c. Risperidone
• d. Haloperidol
• e. Clozapine

Answer 5

d. Haloperidol

Question 6

1. Regarding antidepressants:

• a. Inhibition of MAO only persists while MAO inhibitors are detectable in plasma
• b. Fluoxetine has significant interactions with other antidepressants
• c. Tricyclics are well absorbed orally
• d. Moclobemide acts via MAO-B receptors
• e. Tricyclics are cleared primarily via renal excretion

Answer 6

b. Fluoxetine has significant interactions with other antidepressants

Potent CYP2D6 inhibition

• c. Tricyclics have 50% oral bioavailability
• d. Moclobemide acts via MAO-A receptors
• e. Tricyclics are cleared primarily via hepatic metabolism - only 5% excreted unchanged

Question 7

2. Regarding antidepressants

• a. Fluoxetine is more sedating than tricyclics
• b. SSRIs are more effective in OCD

Answer 7

b. SSRIs are more effective in OCD

• a. Fluoxetine is less sedating than tricyclics
  
  • Does not have histamine antagonism

Question 8

3. Regarding fluoxetine

• a. Serotonin syndrome = muscle weakness, hyperpyrexia and confusion.
• b. It is removed by dialysis
• c. Can cause malignant hyperpyrexia
• d. Is an enzyme inhibitor
• e. Is safe in overdose due to minimal drug interactions

Answer 8

d. Is an enzyme inhibitor

Potent CYP2D6 inhibitor

• a. Serotonin syndrome = muscle excitability (clonus, hyperreflexia etc), hyperpyrexia and confusion.
• b. It is not removed by dialysis
• c. Can cause malignant hyperpyrexia
  
  • This is volatile anaesthetics +/- muscle relaxants
• e. Is safe in overdose due to minimal drug interactions
  
  • Relatively safe in a single drug OD - need to have multiple serotonin agents to cause significant SS.
  • But it has significant drug interactions - see correct answer

Question 9

4. Regarding SSRIs

• a. They are safe in overdose due to minimal drug interactions
• b. Serotonin syndrome = hyperthermia and weak muscles.
• c. They cause malignant hyperpyrexia
• d. Overdose may cause seizures
• e. They are readily removed by dialysis

Answer 9

d. Overdose may cause seizures

• a. Is safe in overdose, but has significant drug interactions (CYP2D6 inhibitor)
  
  • Relatively safe in a single drug OD - need to have multiple serotonin agents to cause significant SS.
• b. Serotonin syndrome = muscle excitability (clonus, hyperreflexia etc), hyperpyrexia and confusion.
• c. Doesn’t cause malignant hyperpyrexia
  
  • This is volatile anaesthetics +/- muscle relaxants
• e. b. It is not removed by dialysis

Question 10

5. Regarding tricyclic antidepressants

• a. Desipramine has mild sedative and mild antiserotonergic effects
• b. Desipramine has mild sedative and strong antiserotonergic effects
• c. Overdose can cause hyperpyrexia and ileus
• d. Some degree of antidepressant effect is usually seen after one week of treatment
• e. They are less efficacious in treating depression than SSRIs

Answer 10

c. Overdose can cause hyperpyrexia and ileus

• Seizures and VT are the classic hallmarks, with QRS widening on ECG. Does have anticholinergic effects so urinary retention, ileus, dry/warm/flushed skin all occur.*
• Sedation/coma occurs before other CNS or CVS effects (typically). I think A and B are wrong as they have a more potent sedation than ‘mild’.*
• Also has some anti-serotonergic effects, but the relative degree of this I am not sure of.*
• I cannot speak to the correct answers for D and E*

Question 11

6. Which of the following is a direct serotonin agonist?

• a. Fluoxetine
• b. Amitriptyline
• c. Moclobemide
• d. Ondansetron
• e. Sumatriptan

Answer 11

e. Sumatriptan

Triptans are 5-HT (serotonin) agonists

• a. Fluoxetine - SSRI
• b. Amitriptyline - TCA
• c. Moclobemide - MAOi
• d. Ondansetron - 5HT antagonist (very low dopamine block)

Question 12

8. The drug that acts by MAO inhibition is

• a. Paroxetine
• b. Sertraline
• c. Trazodone
• d. Moclobemide
• e. Clomipramine

Answer 12

d. Moclobemide

MAO-A inhibitor

• a. Paroxetine - SSRI
• b. Sertraline - SSRI
• c. Trazodone - SARI (serotonin antagonist and reuptake inhibitor)
• e. Clomipramine - TCA

Question 13

7. Regarding SSRIs

• a. They have minimal drug interactions
• b. Have a Vd equal to body water
• c. Block post-synaptic serotonin reuptake
• d. they are preferred in the treatment of obsessive compulsive disorders over TCAs
• e. Are more sedating than TCAs

Answer 13

d. they are preferred in the treatment of obsessive compulsive disorders over TCAs

Question 14

9. The most dangerous drug in overdose is

• a. Imipramine.
• b. Moclobemide
• c. Sertraline
• d. Trazodone
• e. Paroxetine

Answer 14

a. Imipramine. TCA

• b. Moclobemide - MAOi (relatively safe solo but can have fatal interactions with food or other meds)
• c. Sertraline - SSRI (needs other serotonin agents to cause significant SS)
• d. Trazodone - SARI (probably similar to SSRIs - relatively safe in mono-OD, but if taken with other serotonin agents can have potentially fatal effects)
• e. Paroxetine - SSRI (needs other serotonin agents to cause significant SS)

Question 15

10. The cardiac toxicity of tricyclic antidepressants is explained in part by their action as

• a. Alpha agonists
• b. dopamine agonists
• c. antiserotonergics
• d. class Ia antiarrythmics
• e. cholinomimetics

Answer 15

d. class Ia antiarrythmics

Sodium channel blockade