Rectal administration

[7] Rectal administration is sometimes thought of as a safer alternative to intravenous injection of psychoactive substances,[8] which carries a significant risk of infections and illnesses like pulmonary granulomatosis.

[6] The combination of a brief acting time (compared to oral administration) and an unpredictable absorption-rate can, particularly for new users, result in a risk of overdoses.

[10] Some psychoactive substances like substituted amphetamines can induce a strong vasoconstriction in the rectal vasculature and lead to intestinal ischemia.

This leads to the user not knowing if and what substances, by-products or cutting agents are present in their drugs[11] before administering them rectally.

Possible impurities or falsely marketed substances greatly increase the risk of administering illicit drugs rectally.

Administering medication rectally
Insertion of an enema nozzle as it breaches the anal sphincter.
Glycerin ( laxative ) suppositories for insertion into the rectum.
A rectal "bulb" syringe for introducing a small amount of fluid into the rectum.
Enema equipment for introducing a large amount of fluid into the colon via the rectum.