Certain enteric ailments are particularly common among homosexual men. They are primarily infectious diseases and include not only such common venereal diseases as gonorrhea and syphilis but also infections not usually regarded as being sexually transmitted. Among the latter are shigellosis, salmonellosis, giardiasis, and amebiasis. Patients' symptoms are non-specific and seldom helpful in diagnosing particular diseases. The practitioner must be prepared to identify a number of infections with similar presentations that may occur singly or together in gay men. Gonorrhea is probably the most common bacterial infection in gay men. Carriage rates as high as 50% have been reported, and extra-genital carriage is common; this necessitates culturing the urethra, rectum, and pharynx. Procaine penicillin G is the treatment of choice for most patients; spectinomycin is probably the drug of choice in penicillin-sensitive patients. In contrast to other venereal diseases, syphilis may have a characteristic protoscopic presentation. Benzathine penicillin G is the treatment of choice for most patients. Lymphogranuloma venereum causes penile lesions and inguinal lymphadenitis in heterosexual men, whereas homosexual men are more prone to proctitis. The disease may mimic Crohn's disease. Recommended treatment includes tetracycline or sulfamethoxazole-trimethoprim. Shigellosis usually presents as an acute diarrheal illness. Patients generally require only supportive treatment with fluids. Herpes simplex viral infection is difficult to diagnose and has several different presentations, including lumbosacral radiculomyelopathy. Symptomatic treatment with sitz baths, anesthetic ointment, and analgesics is recommended. Venereal warts are believed to be caused by the same virus that causes verrucous warts; they are usually found in the anal canal or around the anal orifice. They are commonly treated with 25% podophyllin solution. Parasitic infections include giardiasis, amebiasis, and pinworm infections. Metronidazole may be used in the treatment of symptomatic giardiasis and amebiasis, but it is not approved for the former indication; quinacrine is approved for giardiasis. Pinworm infestation may be treated with pyrantel pamoate or mebendazole. Cure of enteric diseases in homosexual men must be documented