Starting, switching and stopping antidepressants

Starting an antidepressant

Often you will start to feel better within 1 to 3 weeks of starting an antidepressant, but it can take 6 to 8 weeks to feel the full effect. If you are not feeling better within this time, go back to your doctor — your doctor might need to increase your dose or they might suggest switching to another type of antidepressant.

Finding an antidepressant that works for you is sometimes a matter of trial and error. About one-third of people will lose all or most of their depression symptoms with the first antidepressant they try. Another one-third will lose most or all of their symptoms with subsequent treatments.

Alternatively, your doctor might feel it is worthwhile trying a higher dose of the antidepressant you are already taking.

Switching to another antidepressant

If the first antidepressant you tried hasn’t been effective within 4 to 6 weeks, or if you found the side effects were too troublesome, switching to another one can help. With many antidepressants, you will need to reduce the dose gradually before stopping it.

When stopping some types of antidepressants, you need to wait for a certain period of time before starting another antidepressant. Check with your doctor or pharmacist for more information.

How long should you keep taking your antidepressant?

Once you are feeling better on an antidepressant, you will usually need to keep taking it for another 6 to 12 months to reduce the risk of your depression coming back. Some people (e.g. those who have had multiple episodes of depression before) are advised to keep taking an antidepressant for longer (sometimes for years) to prevent their symptoms coming back.

Talk to your doctor about how long you should keep taking your antidepressant.

Having cognitive behavioural therapy (CBT) at the same time as taking an antidepressant can further reduce the risk of your depression coming back.

Stopping an antidepressant

If you and your doctor have decided it’s time to stop taking your antidepressant, you will usually need to reduce the dose gradually to avoid symptoms such as nausea, dizziness and feeling jittery (discontinuation symptoms). How slowly you need to reduce the dose can depend on several factors, including the type of antidepressant, and how long you have been taking it.

In some cases you need to slowly reduce the dose before you change to another antidepressant too.

Ask your doctor or pharmacist for advice on the best dose reduction plan for you.

For more information

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  • Vos T, Corry J, Haby MM, et al. Cost-effectiveness of cognitive-behavioural therapy and drug interventions for major depression. Aust N Z J Psychiatry 2005;39:683–92. (accessed 18 April 2012).
  • National Collaborating Centre for Mental Health. Depression: the NICE guideline on the treatment and management of depression in adults (updated edition). London: National Institute for Health and Clinical Excellence, 2010. (accessed 9 February 2012).
  • Psychotropic Expert Group. Therapeutic Guidelines: Psychotropic, Version 6. In: eTG complete [Internet]. Melbourne: Therapeutic Guidelines Limited; 2008. (Accessed 9 February 2012)
  • Rossi S, ed. eAMH [online]. Adelaide: Australian Medicines Handbook, 2012. (Accessed 9 February 2012).