1. Stopping, fast and slow
A series of studies conducted by Baldessarini and colleagues has demonstrated that relapse rates are higher for patients who have psychiatric medications stopped abruptly or quickly than for those who have them stopped slowly. This was true for antidepressants, mood stabilisers or antipsychotics (Baldessarini and Tondo, 2019). These studies tell us two things: one, tapering slowly produces better patient outcomes and, two, a proportion of relapse might be accounted for by withdrawal effects mis-classified as relapse (Hengartner and Plöderl, 2021; Récalt and Cohen, 2019).
If relapse was simply the consequence of unmasking the untreated natural history of a patient’s underlying condition, the rate at which a drug was stopped would be immaterial. The rate at which, say, insulin is stopped has no bearing on proximal or ultimate outcomes. For psychiatric drugs the nature of the process of discontinuation itself must be causally related to relapse (Récalt and Cohen, 2019). As it is not plausible that rate of tapering can worsen an underlying condition, it is more likely that rapidly stopping induces withdrawal effects (including effects on sleep, appetite, mood and anxiety) which register on symptom rating scales as a deterioration and are detected as relapse (Hengartner and Plöderl, 2021; Récalt and Cohen, 2019). In addition to this, and perhaps at the same time, abrupt withdrawal can de-stabilise an individual, leading to genuine relapse (Baldessarini and Tondo, 2019).
