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The rectal route of drug administration has been used for many years because drugs may be

readily introduced and retained in the rectal cavity. Rectal administration may be a practical

alternative to oral administration when patients are prone to nausea, vomiting, convulsion,

and, in particular, disturbances of consciousness. Therefore, rectal administration has been

used to deliver many kinds of drugs such as anticonvulsants, analgesics (including narcotics),

antiemetics, antibacterial agents, anesthetics for children, and some anticancer agents. Rectal

drug delivery, on the one hand, is effective because of the extensive rectal vasculature and the

presence of lymphatic vessels in the rectal region. On the other hand, patient acceptability of

rectal administration is poor and drug absorption may be affected by defecation. Further

development and optimization of rectal drug formulations for clinical use may be expected in

the near future. Several reviews concerning rectal drug delivery and absorption have already

been published [1-4].