Agomelatine

MT1/MT2 Agonist + 5HT2C Ant·Psychiatry - Antidepressants

Major Depressive Disorder

MELATONERGICValdoxan25 mg tabletS4TGA

Max Dose

50 mg/day

Half-life

1-2 h

Hepatotoxicity

MONITOR LFTs

Sedation

MILD

Rapid Summary

Overview

Unique 'melatonergic' antidepressant. Re-syncs the circadian rhythm to improve sleep and mood. Devoid of sexual side effects, weight gain, or withdrawal syndromes. Highly liver toxic.

Maximum Dose

Max 50 mg/day (strictly at bedtime).

Clinical Focus

Mandatory rigid liver function testing. You cannot prescribe this drug if the patient refuses blood tests.

Bottom Line

Agomelatine is a unique melatonergic antidepressant with no sexual dysfunction or weight gain, but requires mandatory liver function monitoring due to hepatotoxicity risk.

Formulation & Access

Brand Names

Valdoxan

Oral Routes

Tablets (25 mg).

Prescribing & PBS

Private script only. Not PBS listed in Australia (Expensive out-of-pocket).

Indications & Use

Primary

TGA

Major Depressive Disorder.

Clinical Place

Chosen when patients completely refuse SSRIs due to sexual dysfunction or weight gain, and can afford private scripts.

Quick reference

Class & Role

MT1/MT2 Agonist + 5HT2C Ant — Unique 'melatonergic' antidepressant.

Route / Formulation

Tablets (25 mg). (Valdoxan)

Usual Dose & Max

PO 25 mg NOCTE. If inadequate response after 2 weeks, increase to Max 50 mg NOCTE.

Key Indication Doses

Major Depressive Disorder: PO 25 mg NOCTE. If inadequate response after 2 weeks, increase to Max 50 mg NOCTE. Hepatic Impairment: Absolute contraindication in any form of liver impairment or transaminitis.

Best Uses

Agomelatine is a unique melatonergic antidepressant with no sexual dysfunction or weight gain, but requires mandatory liver function monitoring due to hepatotoxicity risk.

Avoid / Cautions

Any hepatic impairment (e.g., cirrhosis, active hepatitis), transaminases > 3x normal limit. Concurrent use of potent CYP1A2 inhibitors (Fluvoxamine, Ciprofloxacin). Pregnancy Category B1.

Key Risks

Hepatic: Hepatotoxicity, severe transaminitis, fatal liver failure (Rare, but idiosyncratic and highly dangerous). Neurological: Dizziness, somnolence, headache. Endocrine/Metabolic: Zero sexual dysfunction. Weight neutral. Zero withdrawal syndrome.

Key Interactions

Fluvoxamine and Ciprofloxacin inhibit CYP1A2, skyrocketing Agomelatine blood levels and guaranteeing liver damage. AVOID. Smoking induces CYP1A2, significantly dropping blood levels. If patient stops smoking, levels will spike.

Monitoring

LFTs must be performed at Baseline, Week 3, Week 6, Week 12, and Month 6. Stop immediately if ALT/AST > 3x normal limit. Warn patient to report dark urine, pale stool, or yellow sclera immediately.

Clinical Pearl

Do not write the first script without holding a baseline normal LFT result in your hand. If they drink heavily, choose a different drug.

Access

Valdoxan25 mg tablet

Brand: Valdoxan
Formulation: Tablets (25 mg)

Agomelatine

MT1/MT2 Agonist + 5HT2C Ant·Psychiatry - Antidepressants

Major Depressive Disorder

MELATONERGICValdoxan25 mg tabletS4TGA

Max Dose

50 mg/day

Half-life

1-2 h

Hepatotoxicity

MONITOR LFTs

Sedation

MILD

Rapid Summary

Overview

Unique 'melatonergic' antidepressant. Re-syncs the circadian rhythm to improve sleep and mood. Devoid of sexual side effects, weight gain, or withdrawal syndromes. Highly liver toxic.

Maximum Dose

Max 50 mg/day (strictly at bedtime).

Clinical Focus

Mandatory rigid liver function testing. You cannot prescribe this drug if the patient refuses blood tests.

Bottom Line

Agomelatine is a unique melatonergic antidepressant with no sexual dysfunction or weight gain, but requires mandatory liver function monitoring due to hepatotoxicity risk.

Formulation & Access

Brand Names

Valdoxan

Oral Routes

Tablets (25 mg).

Prescribing & PBS

Private script only. Not PBS listed in Australia (Expensive out-of-pocket).

Indications & Use

Primary

TGA

Major Depressive Disorder.

Clinical Place

Chosen when patients completely refuse SSRIs due to sexual dysfunction or weight gain, and can afford private scripts.

Quick reference

Class & Role

MT1/MT2 Agonist + 5HT2C Ant — Unique 'melatonergic' antidepressant.

Route / Formulation

Tablets (25 mg). (Valdoxan)

Usual Dose & Max

PO 25 mg NOCTE. If inadequate response after 2 weeks, increase to Max 50 mg NOCTE.

Key Indication Doses

Best Uses

Agomelatine is a unique melatonergic antidepressant with no sexual dysfunction or weight gain, but requires mandatory liver function monitoring due to hepatotoxicity risk.

Avoid / Cautions

Any hepatic impairment (e.g., cirrhosis, active hepatitis), transaminases > 3x normal limit. Concurrent use of potent CYP1A2 inhibitors (Fluvoxamine, Ciprofloxacin). Pregnancy Category B1.

Key Risks

Key Interactions

Monitoring

LFTs must be performed at Baseline, Week 3, Week 6, Week 12, and Month 6. Stop immediately if ALT/AST > 3x normal limit. Warn patient to report dark urine, pale stool, or yellow sclera immediately.

Clinical Pearl

Do not write the first script without holding a baseline normal LFT result in your hand. If they drink heavily, choose a different drug.

Access

Valdoxan25 mg tablet

Brand: Valdoxan
Formulation: Tablets (25 mg)