Adverse effects of antipsychotics as outcome measures

Antipsychotic drugs are associated with adverse effects that can lead to poor medication adherence, stigma, distress and impaired quality of life.

To review the use of adverse effects of antipsychotic drugs as outcome measures, with a particular emphasis on methodological issues.

Review of data on adverse effects from sources including randomised controlled trials (RCTs), post-marketing surveillance and naturalistic studies.

All have advantages and disadvantages and the best overview comes from considering all sources of data together. Adverse effects are inconsistently reported, hampering cross-study comparisons. Many outcome measures lack clinical meaning. In both naturalistic studies and RCTs adverse effects often account for less treatment discontinuation than lack of efficacy.

Standardisation in the reporting of adverse effects is needed. Patients' subjective experience of medication should be given more consideration. Total discontinuation rates provide a useful global outcome measure that incorporates tolerability and efficacy as well as patient and clinician viewpoints. Patients should be informed of common side-effects prior to treatment and monitored for their occurrence during treatment.