OBJECTIVE Due to risk of serious adverse drug events (ADEs) sotalol use is limited in renal insufficiency and heart failure. To reduce potential life-threatening ADEs, medication safety initiatives that ensure appropriate dosing of sotalol are necessary. Pharmacist-managed renal dosing assessment programmes ensure appropriate dosing of renally eliminated medications. A prospective medication safety evaluation was conducted to assess the need to include sotalol in an existing renal dosing assessment programme as well as the impact of clinical pharmacist assessment on sotalol prescribing. METHODS Patients in a 736-bed community hospital, receiving sotalol during a 6-week period, were prospectively evaluated. Information was collected on indication, dosing, concomitant disease states and medications, renal function, QTc length, symptoms of toxicity and readmissions. Pharmacist recommendations were made when necessary and were followed to determine acceptance rate and patient outcomes. RESULTS Thirty-six patients were prescribed sotalol for atrial tachyarrhythmias. Thirty-two (89%) were dosed inappropriately with respect to renal function. Twenty (56%) had left-ventricular dysfunction as defined by an ejection fraction of ≤ 40%. At time of initial assessment, 15 (42%) were exhibiting signs of potential sotalol toxicity. Pharmacists provided recommendations regarding discontinuation or dosage adjustment on 32 patients with a 38% full and a 12% partial acceptance rate. All-cause readmission rates for patients receiving appropriate therapy, including those after pharmacist recommendations were accepted (Group A; n=16), were compared to those remaining on inappropriate therapy (Group B; n=20). Readmission rates within 6 months differed between groups (31% for Group A, 55% for Group B; P=0.095, odds ratio 3.7). CONCLUSIONS This medication safety evaluation suggests the need for pharmacist assessment in patients receiving sotalol. Dosage adjustment or avoidance in patients with renal insufficiency, heart failure and other relative contraindications is often necessary to avoid toxicity. Sotalol was inappropriately prescribed in the majority of patients secondary to renal insufficiency. Based on this evaluation, it was recommended to add sotalol to the institution's pharmacist-managed renal dosing adjustment programme. Ensuring clinical pharmacist assessment when sotalol is prescribed can help reduce potential life-threatening ADEs and hospital readmissions.