Affective Disorders and Antidepressant Pharmacology

Comprehensive practice questions covering the pathophysiology of depression, antidepressant drug classes (SSRI, SNRI, TCA, MAOI), and related clinical syndromes like Serotonin Syndrome and Fibromyalgia.

According to the neurotropic hypothesis of major depression, what specific factor regulates neural plasticity and neurogenesis?

Nerve growth factors, specifically brain-derived neurotrophic factor ($BDNF$).

Which three neurotransmitters are involved in the Monoamine Hypothesis of Depression?

Serotonin ($5HT$), norepinephrine ($NE$), and dopamine ($DA$).

Which neuroendocrine axis disturbance is most common in Major Depressive Disorder ($MDD$)?

Disturbance of the hypothalamic-pituitary-adrenal ($HPA$) axis, characterized by increased $CRH$ secretion and chronically elevated cortisol.

Why is there a delay or 'therapeutic lag' in the effects of antidepressant drugs despite immediate increases in amine levels?

The delay is due to the time required ($2$ weeks or more) to synthesize neurotrophic factors and increase synaptic connectivity.

What is the primary mechanism of action for Selective Serotonin Reuptake Inhibitors ($SSRI$)?

Blockade of the serotonin transporter ($SERT$), resulting in longer serotonin dwell time at the synapses.

What specific Black Box warning is associated with SSRIs and other antidepressants?

Use in children due to the risk of suicidal ideation.

What are the common symptoms of sudden withdrawal from an SSRI?

Nausea, vomiting, dizziness, hypertension ($HTN$), and hyperreflexia.

What is the oral activity half-life range for SSRIs according to the lecture notes?

Half-lives range from $15-75\,h$.

Which medications are listed as first-line treatments for Panic Disorder?

Escitalopram, Sertraline, and Paroxetine with psychotherapeutic intervention.

How do Serotonin-Norepinephrine Reuptake Inhibitors ($SNRI$) differ from Tricyclic Antidepressants ($TCA$) regarding receptor affinity?

While both block $SERT$ and $NET$, SNRIs do not have much affinity for other receptors (such as alpha-1, muscarinic, or histamine) compared to TCAs.

Which potent pain mediator neuropeptide is found in increased levels in the cerebrospinal fluid of patients with Fibromyalgia?

Substance P.

Why is an overdose of Tricyclic Antidepressants ($TCA$) potentially lethal?

Due to effects on sodium ($Na^+$) channels causing arrhythmia and hypotension; a weekly dose is enough for a deadly overdose.

Which Atypical Antidepressant is used specifically for smoking cessation?

Bupropion (Wellbutrin).

What are the three clinical categories used to identify Serotonin Syndrome?

Mental status changes (Cognitive Changes), Autonomic Instability (Autonomic Hyperactivity), and Neuromuscular Hyperactivity (Neuromuscular Abnormalities).

What is the mechanism of action for the postpartum depression medication Zuranolone (Zurzuvae)?

It is a positive allosteric modulator of $GABA_A$ receptors that increases $GABA$ activity.