Antidepressants

Question 1

SSRIs

Answer 1

-Most commonly prescribed for depression
-Selectively inhibits 5-HT (serotonin) reuptake thus increasing serotonin in synapse
-Advantage over tricyclics and MAOIs - little or no effect on cardiovascular system

DRUG: Sertraline (zoloft)

May take 2-6 weeks for effects

Indications: MDD, Bipolar disorder, ED, OCD, Panic attacks

Adverse: Sexual dysfunction, weight gain

Question 2

SNRIs

Answer 2

Venlafaxine (Effexor)

-Fewer adverse effects than TCAs and MAOIs

Question 3

Tricyclic Antidepressants (TCA)

Answer 3

Largely replaced as first-line by SSRIs and SNRIs
-Now considered second-line

DRUG: Amitriptyline

Blockade of NE reuptake
Blockade of 5-HT reuptake
Receptor block of muscarinic (cholinergic) receptors (a1, H1) which leads to adverse effects

ADVERSE: sedation (wears off in 1-2 weeks) , anticholinergic effects and orthostatic hypotension

CAUTION in pts with cardiac dysrhythmias and seizures

TCA overdose is lethal. Death from seizures or cardiac dysrhythmias. No antidote for acute toxicity. Charcoal can help.

Question 4

Monoamine Oxidase Inhibitors (MAOIs)

Answer 4

-Treatment for depression not responsive to other drugs
-Inhibit MAO enzyme in CNS and peripheral tissues
-Risk for hypertensive crisis when taken with tyramine (cheese effect)

Adverse effects and interactions:
Orthostatic hypotension
Ingestion of tyramine may lead to hypertensive crisis (cheese effect)

AVOID food with tyramine (aged, mature cheese)

SSRI to MAOI switch: must be 2-5 week wash out
MAOI to TCA/SSRI switch: **2 week wash out* also maintain diet restriction for 2 weeks after MAOI cessation