Rectal mucosa damage

De Muynck C, Cuvelier C, Van Steenkiste D, et al. Rectal mucosa damage in rabbits after subchronical application of suppository bases. Pharm Res 1991 8 945-950. 

Although intravenous diazepam is the preferred route, the undiluted intravenous solution of diazepam can be given rectally, and is effective in the emergency management of seizures in children (29). Rectal gel is an alternative, and can be given by non-medical personnel (30). Adverse effects of rectal diazepam are rare and mild. Animal studies and clinical experience have not shown damage to the rectal mucosa. 

Sodium salicylate and 5-methoxysalicylate increased the absorption of insulin. Sodium glycocholate was more effective than sodium taurocholate but less effective than sodium-deoxycholate and PE-9-laurylether in enhancing rectal insulin absorption in rabbits. The role of disodium EDTA in the enhancement of rectal drug absorption, along with the damaging effects on the rectal mucosa, has been described for several drugs. ... 

Local anaesthetics are included in haemorrhoidal preparations to relieve pain, burning and itching. Use should be restricted to the perianal region and lower anal canal they should not be used in the rectum as there is little sensory tissue there and the anaesthetic can be readily absorbed through the rectal mucosa to cause potentially toxic systemic effects. Local anaesthetics are also absorbed through damaged skin. 

Administration of liquid rectal preparations requires a squeezable bottle (see Sect. 24.4.4.1), a bag (Sect. 24.4.13.2) or a syringe (see Sect. 24.4.16), with a rectal cannula (see Fig. 24.10). This cannula is preferably of flexible material to prevent damage to the rectal mucosa. This is less important with short cannulas than with long ones. An enema bag has a long flexible tube cannula. This cannula should be lubricated or should be made of slippery material to ease insertion. The cannula should have a rubber one-way check valve when respiration is possible (with enema bottles, not with enema bags). 

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