No medications have been indicated for the treatment of anorexia nervosa (AN). Nonetheless, individuals with AN are frequently treated pharmacologically. The present study maps nationwide pharmacotherapy two years before to five years after first AN diagnosis. We identified all medication prescriptions in a national register-based study of patients with a first diagnosis of AN between 1998 and 2011, and age and gender matched controls (1:10). Medication classes were compared using odds ratios (OR) between patients and controls; between patients below and above 15 years; between patients with and without comorbidity; and between those diagnosed before or after 2005. The odds of pharmacotherapy were increased in patients for all classes of medication except a small residual class. Highest odds were found for alimentary (OR 2.8, p < 0.001) and psychopharmacological (OR 5.5, p < 0.001) medication. The former peaked one year prior to first diagnosis and the latter one year after. Older patients had increased risk of almost all medication classes with cardiovascular medication showing a fivefold OR (p < 0.001). Patients with psychiatric comorbidity had a threefold OR for psychopharmacological medication (p < 0.001) compared to patients without psychiatric comorbidity. Calendar year showed few and small differences. The extended use of all medication classes both prior to and after first diagnosis of AN highlights the severe cause and complexity of AN. The results encourage clinical caution of pharmacotherapy, highlight the need for pharmacotherapy guidelines for AN, and emphasize the urgency of research in pharmacotherapy in AN. •Pharmacotherapy is common in the treatment of anorexia nervosa.•A three-fold increase of alimentary drugs peaks one year prior to first diagnosis.•A five-fold increase of psychopharmacotherapy peaks one year after first diagnosis.•Elevated pharmacotherapy reflects the complex treatment needs of patients.•Pharmacotherapy guidelines and research are urgently needed in anorexia nervosa.