To evaluate the effectiveness of haloperidoll as an adjunctive treatment for resistant anorexia nervosa restricting subtype (AN-R). Thirteen outpatients with treatment-resistant AN-R were treated for 6 months with haloperidol in addition to standard treatment. Treatment resistance was defined as persistent and resistant anorectic symptoms despite multiple standard therapies. Assessments were carried out at baseline and after 1, 3, and 6 months with the Eating Disorder Inventory (EAT), the Eating Attitude Test (EAT), and the Clinical Global Impression and Improvement Scale (CGI-I). Significant change from baseline to end point was observed on EDI total score (p =.02) and on the subscales Drive for Thinness (p =.009), Bulimia (p =.01), and Interoceptive Awareness (p =.02), as well as on the EAT (p =.009) and CGI scores (p =.001). Body mass index changed significantly from baseline (15.7 +/- 1.9) to end point (18.1 +/- 2.5; p =.03). These preliminary data suggest that low doses of haloperidol might be effective as an adjunctive treatment for patients with severe AN-R. Larger controlled studies are warranted to confirm these data. Copyright 2003 by Wiley Periodicals, Inc.