- Prescribing Advice for GPs - https://www.prescriber.org.uk -

New antidepressant class

Agomelatine (Valdoxan®) has been launched in the UK for the treatment of major depressive episodes in adults.

This new drug is a melatonin receptor agonist and serotonin-2c antagonist. The initial dose is 25mg daily taken at night and this dose may be doubled after two weeks if there is no symptom improvement.

The drug is not recommended in people under 18 years of age and those with active liver disease. Caution is required in people aged over 65 years and those who consume large quantities of alcohol. Liver function should be monitored at 12 and 24 weeks and treatment stopped if serum transaminases exceed three times the upper limit of normal.

Common side effects include gastrointestinal disturbances (nausea, diarrhoea, constipation and abdominal pain), headache, dizziness, insomnia, somnolence and liver function changes.

Agomelatine is available in 25mg tablets in packs of 28 at a cost to the NHS of £38.53. A month of treatment will therefore cost £38.53 to £77.06 depending on the daily dose.

Action: Clinicians should be aware of this new drug. It's place in therapy is currently unclear and it may be prudent to limit use to specialists and continue to follow existing guidelines.