Pharmacokinetics and rectal bioavailability of hydrocortisone acetate after single and multiple administration in healthy subjects and patients

The pharmacokinetics and bioavailability of hydrocortisone after rectal adm inistration of a hydrocortisone acetate foam were determined after single a nd multiple dosing in healthy subjects as well as in patients with inflamma tory bowel disease. Endogenous hydrocortisone was suppressed by dexamethaso ne administration. Plasma levels were compared with those observed after in travenous administration of hydrocortisone. Only a very small part of the r ectal dose (100 mg) was absorbed: the mean absolute bioavailiability was 3. 1% in healthy volunteers and 4.5% in patients. There was substantial inters ubject variability. Although maximum hydrocortisone levels after single or multiple doses were significantly higher(about 70%) in the patient group, t he systemic bioavailability is very low so that the risk of systemic side e ffects after rectal administration of hydrocortisone acetate foam has to be considered very low. (C) 2001 the American College of Clinical Pharmacolog y.