Hyperbolic dose reduction

When PET imaging data was used to examine serotonin receptor occupancy at various doses of SSRIs, it was found that the relationship between dose and occupancy was not linear. Studies recommended that reducing SSRI doses “hyperbolically” would reduce the risk of discontinuation symptoms.

This hyperbolic style of dose reduction involves making smaller decreases in the dose towards the end of the withdrawal period and is often applied when reducing and stopping benzodiazepines. 

This advice has been adopted by the latest NICE guidelines, due to be released imminently and will recommend reducing SSRI dosages proportionally rather than by a regular fixed amount or through a linear approach. As an example, the guidelines recommend reducing a dose in steps of 75 or 50 per cent of the previous dose, so it could take several weeks or even months to complete a full withdrawal. 

The guidelines highlight that the speed and duration of withdrawal should be led by the person taking the medication, so the prescriber needs to have an open discussion with the individual and a joint decision made.

The NICE guidelines recommend continuing medications for at least six months after the remission of symptoms. The guidelines also emphasise the importance of the individual being monitored during the withdrawal period for any mood changes and discontinuation symptoms. The frequency of this monitoring will be decided dependent on clinical need. 

The following case study involves an individual who had a successful antidepressant withdrawal using hyperbolic dose reductions.