Antipsychotic dose reduction and discontinuation versus maintenance treatment in people with schizophrenia and other recurrent psychotic disorders in England (the RADAR trial): an open, parallel-group, randomised controlled trial
Study (n=253) found gradual, flexible antipsychotic reduction had no effect on social functioning (measured using the Social Functioning Scale) when compared to continued maintenance treatment, but was associated with severe relapse in 25% (v 13% maintenance) by 24 months.
Source:
The Lancet Psychiatry
SPS commentary:
The original hypothesis that dose reductions would improve social functioning without resulting in significantly more relapses was not confirmed in this study. A related comment notes this confirms earlier findings, but avoided the important bias of dose reductions being too rapid and introducing possible rebound effects. However a selection bias was possible, as only 253 of an original 4,157 people screened could be randomised, and this may be due in part to inclusion of those with relatively mild illness. It also notes that the median drug doses were standard and associated with only mild side effects, so it is questionable why dose reductions were attempted.
The comment discusses other research in the field, and notes the lesson to be taken is that ‘all patients should be informed that a substantial dose reduction or discontinuation of antipsychotics is associated with an increased risk of relapse, and that reductions in side-effects are unclear.’ Individual decisions should be based on the patient’s wishes, life situation and current side effects, and clinicians may want to consider severity of the index episode before considering this as an option. Any dose reductions should be done very slowly to allow the brain to adapt after stopping dopamine blockade.