THERAPEUTICS

Brands

• Remeron, Remeron SolTab

Generic?

• Yes

Class

• Tetracyclic antidepressant

Commonly Prescribed for

(FDA approved in bold)

• Major depressive disorder

• Tension-type headache prophylaxis

• Post-traumatic stress disorder (PTSD)

• Panic disorder

• Fibromyalgia

• Neuropathic pain

• Phantom limb pain

• Antiemetic

How the Drug Works

• Mirtazapine enhances central noradrenergic and serotonergic activity via presynaptic α2-receptor blockade. Mirtazapine is an antagonist of 5-HT2, 5-HT3, H1, α1-, α2- adrenergic, and muscarinic receptors. Mirtazapine has no significant affinity for the 5-HT1A and 5-HT1B receptors

How Long Until It Works

• Depression: 2 weeks but up to 2 months for full effect

If It Works

• Continue to use and monitor for AEs. May continue for 1 year following first depression episode or indefinitely if> 1 episode of depression

If It Doesn't Work

• Increase to highest tolerated dose. Change to another agent or add a second agent

Best Augmenting Combos for Partial Response or Treatment-Resistance

• For some patients, low-dose polytherapy with 2 or more drugs may be better tolerated and more effective than high-dose monotherapy

Tests

• Monitor transaminase, serum sodium, and CBC

ADVERSE EFFECTS (AEs)

How the Drug Causes AEs

• Through serotonin, histamine, adrenergic, muscarinic receptor antagonism throughout the body. Most AEs are dose- and timedependent

Notable AEs

• Somnolence, dizziness, constipation, dry mouth, increased appetite, weight gain, increased cholesterol, akathisia

Life-Threatening or Dangerous AEs

• Serotonin syndrome

• Rare hepatitis

• Rare activation of mania or suicidal ideation

• Rare worsening of coexisting seizure disorders

• Hyponatremia

• Agranulocytosis

Weight Gain

• Problematic

Sedation

• Common

What to Do About AEs

• For minor AEs, lower dose, titrate more slowly, or switch to another agent. For serious AEs, lower dose and consider stopping, taper to avoid withdrawal symptoms