Key Psychopharmacology

Question 1

Serotonin Syndrome

Answer 1

Caused by increased serotoniergic receptor activation especially 5HT2

Medications that increase serotonin through enhanced release, reuptake or inhibited metabolism.

• SSRIS
• TCAs
• MAOis
• Trazodone

Question 2

Anticholinergic Toxicity

Answer 2

Additive effects of decreased ACh through inhibition or blockage of muscarinic receptors.

Risk of confusion and falls in the elderly.

• TCAs
• Benztropine
• Diphenhydramine
• Clozapine
• Quetiapine

Question 3

QT Interval Prolongation

Answer 3

Mecations causing additive QT prologation - may lead to Torsades de pointes

• Haloperidol
• Ziprasidone
• TCAs
• Antiarrythmic agents
• Macrolide antibiotics

Question 4

Increase Seizure Risk

Answer 4

Lowering of seizure threshold

• Bupropion
• Alcohol
• Traumatic brain injury
• Benzodiazepine withdrawl

Question 5

Increased Bleeding Risk

Answer 5

Blocked serotonin re-uptake in platelets leading to reduced aggregation

SSRIs + NSAIDs or anticoagulants

Question 6

Decreased Antipsychotic Plasma Concentrations

Answer 6

Induction of CYP1A2

• Cigarette smoking
• CYP1A2 substrates - clozapine and olanzapine

Question 7

Decreased Efficacy of Oral Contraceptives

Answer 7

Induction of CYP450 enzymes

Carbamazepine

Question 8

Lithium Toxicity

Answer 8

Increased serum lithium concentration through decreased renal exception or increased reabsorption

Lithium

NSAIDS

Thiazide diurectics

ACEi

ARBs