F50 vs F55
F55 — Abuse of non-dependence-producing substances (e.g. laxatives)
Distinguish laxative or other substance misuse occurring as an eating disorder's compensatory behaviour from a stand-alone pattern of non-dependence-producing-substance abuse.
This is just for your own thinking. It is never submitted, sent, or stored anywhere — it disappears the moment you leave or reload this page.
Show overlap — what both share
Both can present as persistent, excessive laxative (or similar substance) use that the person continues despite advice to stop.
Show decisive evidence
- F50's bulimia nervosa requires recurrent binge eating with a sense of loss of control, with the substance use functioning specifically as compensatory behaviour to prevent weight gain after a binge.
- F55's laxative abuse occurs without a binge-eating pattern and without the body-image-driven restriction/compensation cycle that defines bulimia nervosa.
- Checking for the presence of recurrent binge eating and a body-image/weight-control motive tied specifically to compensating for binges is the decisive step.
- A belief that the substance is generally 'necessary' for health or cleansing, unconnected to binge eating, points toward F55 rather than F50.
What weakens F50: Evidence of recurrent binge eating with compensatory intent weakens F55 and favours F50; evidence of substance use with no binge-eating pattern at all weakens F50 and favours F55.
Show duration / course
Both can be persistent over months to years; the decisive factor is the presence or absence of a binge-eating pattern, not duration.
Show exclusions / context
A vignette should be checked for recurrent binge eating and a weight-control motive specifically tied to compensating for binges, not just for the presence of laxative or substance use itself.
Show information still needed
Whether a recurrent binge-eating pattern with loss of control is present, and whether the substance use functions as compensation for it.
Show the common trap
Treating any persistent laxative or similar substance misuse as automatically part of an eating disorder, without checking for an actual binge-eating pattern.
Mini challenge — practise this distinction
Apply the discriminating evidence above to a fresh case before checking the full feedback.