Rectal drug delivery

Abstract

In general, rectal drug delivery refers to the administration and absorption of drugs from a suitable pharmaceutical product through the rectal mucosa, in order to achieve a systemic effect of the drug. However, the term is also used to refer to the administration of drugs or substances into the rectum for local effects, colon cleansing (i.e., emptying), or diagnostic purposes. Rectal route of drug administration has a long history, comparable with the oral route. In ancient times, suppositories and enemas were commonly used by physicians for the treatment of multiple conditions, from constipation to diarrhea. Nowadays, the rectal route is frequently used either for local or systemic effects. There are many therapeutic reasons for its use, most of them related to physical, physiological, or organoleptic reasons that make rectal administration preferable to the oral route, despite the latter being the physiological route of entry of substances into the body.