starting and monitoring antidepressant treatment

Last edited 08/2018

Starting and Monitoring antidepressant treatment

When an antidepressant is to be prescribed in routine care, it should be a selective serotonin reuptake inhibitor (SSRI), because SSRIs are as effective as tricyclic antidepressants and are less likely to be discontinued because of side effects.

  • explore any concerns the person has about taking medication and provide information, including:

    • the gradual development of the full antidepressant effect
    • the importance of taking medication as prescribed and the need to continue beyond remission
    • potential side effects and drug interactions
    • the risk and nature of discontinuation symptoms (particularly with drugs with a shorter half-life, such as paroxetine and venlafaxine)
    • the fact that addiction does not occur

  • for people who are not considered to be at increased risk of suicide, normally see them after 2 weeks. See them regularly, for example every 2-4 weeks in the first 3 months, and then at longer intervals if response is good

  • for people who are considered to be at increased risk of suicide or are younger than 30 years, normally see them after 1 week and then frequently until the risk is no longer clinically important

  • if a person experiences side effects early in treatment, provide information and consider:
    • monitoring symptoms closely if side effects are mild and acceptable to the person or
    • stopping or changing to a different antidepressant if the person prefers or
    • in discussion with the person, consider short-term concomitant treatment with a benzodiazepine if anxiety, agitation and/or insomnia are problematic (except in people with chronic symptoms of anxiety); this should usually be for no longer than 2 weeks in order to prevent the development of dependence

  • people who start on low-dose TCAs and have a clear clinical response can be maintained on that dose with careful monitoring

  • If the person's depression shows no improvement after 2 to 4 weeks with the first antidepressant, check that the drug has been taken regularly and in the prescribed dose

  • if response is absent or minimal after 3-4 weeks of treatment with a therapeutic dose of an antidepressant, increase support and consider:
    • increasing the dose in line with the summary of product characteristics (SPC) if there are no significant side effects or
    • switching to another antidepressant if there are side effects or if the person prefers

  • if there is some improvement by 4 weeks, continue treatment for another 2-4 weeks. Consider switching antidepressants if:
    • response is still not adequate or
    • there are side effects or
    • the person prefers to change drug


For more detailed guidance then refer to full NICE guideline (1).


  1. NICE (April 2018). Depression
  2. Anderson IM et al (2000). Evidence-based guidelines for treating depressive disorders with antidepressants: a revision of the 1993 British Association for Psychopharmacology guidelines. J Psychopharmacol, 14, 3-20.
  3. MeReC Briefing (2005); 31:1-8.