THERAPEUTICS

Brands

• Viibryd

Generic?

• No

Class

• Selective serotonin reuptake inhibitor (SSRI)

Commonly Prescribed for

(FDA approved in bold)

• Major depressive disorder

• Generalized anxiety disorder

• Chronic pain

How the Drug Works

• It blocks the serotonin transporter (SERT) (Ki = 0.1 nM) and is a presynaptic 5-HT1A partial agonist

How Long Until It Works

• 2 weeks to 2 months for full effect

If It Works

• Continue to use and monitor for AEs

If It Doesn't Work

• Increase to highest tolerated dose. Consider adding a second agent or changing to another one

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

• None available

ADVERSE EFFECTS (AEs)

How the Drug Causes AEs

• By increasing serotonin on non-therapeutic responsive receptors throughout the body. Most AEs are dose- and time-dependent

Notable AEs

• Incidence ≥ 5%: insomnia, nausea, vomiting, diarrhea

Life-Threatening or Dangerous AEs

• Serotonin syndrome

• Rare activation of mania or suicidal ideation, especially during the initial few months

• Angle-closure glaucoma

• Rare worsening of existing seizure disorders

• Rare hyponatremia and abnormal bleeding

Weight Gain

• Unusual

Sedation

• Not unusual

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

Best Augmenting Agents to Reduce AEs

• Cyproheptadine can be used for serotonin syndrome by blocking 5-HT receptors and SERT

DOSING AND USE

Usual Dosage Range

• 40mg once daily

Dosage Forms

• Tablet: 10, 20, 40mg

How to Dose

• Initial 10mg daily for 7 days, followed by 20mg daily for 7 days, then increase to 40mg daily