[Bioavailability of sotalol in short bowel syndrome]

The individual bioavailability of enterally administered drugs is usually uncertain in case of reduced bowel length. Routine measurements of plasma concentrations are available only for a small number of drugs. The daily dose recommended by the manufacturers may result in subtherapeutic plasma concentrations when given to such patients.

In 2 patients with hemodynamically relevant atrial fibrillation and reduced gut length application of increasing sotalol doses was initiated. For the assessment of the individual bioavailability plasma concentrations were measured via HPLC immediately before and 2 hours after enteral application of sotalol. Judging by clinical criteria both patients were treated successfully. Even in the patient with severe short bowel syndrome (stomach, duodenum and 50 cm jejunal remnant) doubling of the daily dose led to a substantial increase in plasma concentrations.

Effective enteral medication with sotalol in patients with short residual bowel is possible. Normal plasma concentrations can be achieved by administering doses according to the manufacturers' instructions. In case of severe short bowel syndrome, the measurements of plasma concentrations may be beneficial in supervising dose-adjustment.