Many drugs can be absorbed across the rectal mucosa. Administration of a medication per rectum may be appropriate under certain circumstances.

When to consider rectal administration of a drug:

(1) Availability of a rectal formulation with reliable absorption.

(2) Oral or other routes of administration not available:

(2a) persistent vomiting

(2b) unconsciousness

(2c) high risk of aspiration

(2d) esophageal or gastrointestinal obstruction

(2e) severe needle phobia

(2e) lack of accessible blood vessels

(3) Practical and economic considerations:

(3a) lack of trained personnel for parenteral administration

(3b) lack of resources for parenteral administration

(3c) poor socioeconomic conditions

(4) No contraindications to rectal administration, such as diarrhea or severe colitis


Ways to administer a drug per rectum:

(1) rectal suppository

(2) rectal gel

(3) enema (effective but messy)

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