The last few milligrams of venlafaxine may matter most when tapering
Brain imaging of related drugs shows a dose's effect rises steeply at low doses then flattens, which is why some guidance shrinks each cut as the dose falls. No trial has tested this for venlafaxine.
What the study found
Halving a low dose removes more drug effect than halving a high one
Brain scans show the share of serotonin transporters a drug blocks rises steeply at low doses, then flattens. Hence hyperbolic tapering: cuts that shrink as the dose falls, ending far below the smallest pill. UK psychiatric guidance applies it to venlafaxine, down to counting beads.
The caveat · Based on scans of other drugs
The argument comes from imaging of SSRIs, not venlafaxine, and from receptor occupancy rather than from a trial that measured how people felt. No randomised trial has compared hyperbolic with straight-line tapering of venlafaxine.
What we don't know
The argument comes from imaging of SSRIs, not venlafaxine, and from receptor occupancy rather than from a trial that measured how people felt. No randomised trial has compared hyperbolic with straight-line tapering of venlafaxine.