How long do SSRIs take to work?

SSRIs are generally described as taking several weeks to reach their full effect. It is common to notice side effects before you notice benefit, which is an uncomfortable order of events and one of the most common reasons people stop early.

Some improvement in sleep, appetite or energy may appear sooner than a change in mood. If nothing at all has shifted after several weeks at a steady dose, that is information for your prescriber rather than a verdict on the medicine: dose, timing and choice of medicine are all things a clinician can adjust.

Stopping suddenly is specifically advised against, because it can cause withdrawal effects. Any change to how or whether you take it belongs in a conversation with the person who prescribed it. If you have thoughts of harming yourself, that is urgent: contact your local emergency number, or in the US call or text 988.