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Approximately 9% of an oral dose of xamoterol is absorbed from the gastrointestinal tract. The low absorption rate of the drug results from its hydrophilic nature, which limits penetration of the gastrointestinal wall to the bloodstream, but not absorption from extensive hepatic phase I metabolism. The only metabolism appears to be sulfate conjugation of the 4-hydro group, occurring primarily in the gut wall after oral administration and in the liver after intravenous administration. Xamoterol is cleared from the blood by renal excretion, and some tubular excretion may be involved. After oral administration, 56% of the conjugate, which is pharmacologically inactive, is excreted in urine. There is no evidence of enterohepatic circulation.