Effect of Nonsteroidal Anti-inflammatory Drugs on the Absorption of Macromolecular Drugs in Rat Rectum

Abstract

The effect of three nonsteroidal anti-inflammatory drugs (NSAID), indomethacin, phenylbutazone and dicolofenac sodium, on the absortion of water-soluble drugs with various molecular weights through the rectal membrane was evaluated by using an in situ perfusion technique. ¹⁴C-Inulin, ¹²⁵I-insulin, ¹²⁵I-polyvinyl pyrrolidone (PVP) and ¹²⁵I-albumin were selected as marker drugs. NSAID increased the absorptions of inulin, insulin and PVP, but not that of albumin. It is suggested that macromolecular drugs with a molecular weight of less than 35000 are able to penetrate through the rectal membrane in the presence of NSAID.