Dapoxetine

Key facts

• Dapoxetine (the ingredient in Priligy and combination products) is a short-acting SSRI, taken only when sex is planned rather than daily like antidepressant SSRIs.
• Take it 1 to 3 hours before sex with a full glass of water; do not take more than one dose in 24 hours.
• Dapoxetine can cause fainting or a sudden drop in blood pressure on standing, most often after the first dose. Take it sitting or lying down where possible, and stand up slowly afterward.
• Avoid alcohol completely, and be cautious with driving or operating machinery until you know how the medicine affects you.

What dapoxetine treats

Dapoxetine treats premature ejaculation in adult men, where ejaculation happens sooner than a man or his partner would like and causes distress. It is taken only on the day sex is expected. It is not a daily antidepressant, does not treat erectile dysfunction on its own, and does not increase desire, though it is sometimes combined with a PDE5 inhibitor in a single tablet.

How dapoxetine works

Ejaculation timing is partly controlled by serotonin signalling in the brain and spinal cord. Dapoxetine blocks the reuptake of serotonin, raising its level quickly and briefly, which delays the ejaculatory reflex. Unlike antidepressant SSRIs, it is absorbed and cleared from the body fast, so it is taken on demand rather than every day.

Before you take it

• Do not use dapoxetine if you have significant heart disease, including heart failure, or a history of fainting.
• Do not combine it with other antidepressants, MAOIs, or other serotonergic drugs such as certain migraine medicines, tramadol or St John's wort; the combination can cause serotonin syndrome.
• Tell your prescriber about liver disease, epilepsy, bipolar disorder or mania, and any medicine that lowers blood pressure.
• It is for men only and must not be used by women or children.

Side effects

Common effects include nausea, headache, dizziness and diarrhoea, which are more likely after the first few doses.

Stop and seek urgent medical care for any of these:

• Fainting, or feeling about to faint, particularly on standing up.
• Palpitations, chest pain or an irregular heartbeat.
• Sudden mood changes, agitation, or thoughts of self-harm.
• Signs of serotonin syndrome: confusion, high fever, muscle twitching or stiffness.

Safety essentials

• The first-dose fainting risk is the defining safety issue: take your first dose when you can sit or lie down for a few hours afterward, always with a full glass of water, and tell your prescriber if you feel light-headed.
• Never combine dapoxetine with alcohol; it increases both dizziness and the risk of fainting.
• Avoid driving or using machinery for at least a few hours after each dose, especially until you know how you respond.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.