Psychological Medicine

Review Article

Olfactory reference syndrome: a systematic review of the world literature

M. Beguma1 c1 and P. J. McKennaa2

a1 Behavioural Psychotherapy Service, NHS Forth Valley, Scotland

a2 Benito Menni CASM, Sant Boi, Barcelona and CIBERSAM, Spain


Background The nosological status of olfactory reference syndrome (ORS) is a matter of debate and there is uncertainty as to what treatments are effective.

Method The world literature was searched for reports of cases of ORS. Clinical, nosological and therapeutic information from cases meeting proposed diagnostic criteria for the disorder was summarized and tabulated.

Results A total of 84 case reports (52 male/32 female) were found. Age of onset was <20 years in almost 60% of cases. Smell-related precipitating events were recorded in 42%. Most patients could not smell the smell or only did so intermittently. Authors of the reports expressed reservations about the delusional nature of the belief in slightly under half of the cases. Over two-thirds were improved or recovered at follow-up, with the disorder responding to antidepressants and psychotherapy more frequently than to neuroleptics.

Conclusions ORS is a primary psychiatric syndrome that does not fit well into its current classification as a subtype of delusional disorder, both in terms of its nosology and its response to treatment.

(Received October 06 2009)

(Revised March 31 2010)

(Accepted April 19 2010)

(Online publication June 09 2010)


c1 Address for correspondence: Dr M. Begum, NHS Forth Valley, Behavioural Psychotherapy Service, 2 the Bungalows, Stirling Rd, Larbert FK5 4SD, Scotland. (Email: