Trichotillomania is characterized by repetitive pulling that causes noticeable 
hair loss. Data on the pharmacological treatment of trichotillomania are 
limited, with no clear first-line agent. The aim of the current study was to 
determine the efficacy and tolerability of inositol in adults with 
trichotillomania. A total of 38 individuals (35 women; mean age: 28.9±11.4) with 
trichotillomania entered a 10-week, double-blind, placebo-controlled trial to 
evaluate the safety and efficacy of inositol (dosing ranging from 6 to 
18 g/day). Patients were assessed using the Massachusetts General Hospital Hair 
Pulling Scale, the NIMH Trichotillomania Severity Scale, Clinical Global 
Impression Scale, and measures of depression, anxiety, and psychosocial 
functioning. Outcomes were examined using a linear mixed-effects model. Patients 
assigned to inositol failed to show significantly greater reductions on primary 
or secondary outcomes measures compared with placebo (all P>0.05). At study 
endpoint, 42.1% of patients were 'much or very much improved' on inositol 
compared with 35.3% on placebo. This is the first study assessing the efficacy 
of inositol in the treatment of trichotillomania, but found no differences in 
symptom reductions between inositol and placebo. Future studies should examine 
whether inositol may be beneficial in controlling pulling behavior in a subgroup 
of individuals with trichotillomania.