Other implicated antibiotics include co-trimoxazole, doxycycline, ofloxin, and chloramphenicol. Some other medicines that can produce an acnelike eruption include adrenocorticotrophic hormone, nystatin, isoniazid, itraconazole, hydroxychloroquine, naproxen, mercury, and the antipsychotic olanzapine. Lithium is another psychotropic medication that frequently induces a follicular acneiform eruption. Gram-negative folliculitis, a persistent papulopustular eruption, may be a complication in patients on prolonged antibiotic treatment for acne vulgaris or rosacea. It is more common in male patients.
Treatment consists of the appropriate antibiotic coverage for the causative organism.
Isotretinoin may sometimes be an effective alternative or adjunctive treatment. Pityrosporum folliculitis is another infectious folliculitis that presumably is caused by a host reaction to the yeast Malassezia furfur , previously named Pityrosporum ovale , a normal human skin commensal. It appears primarily on the trunk and upper extremities of late adolescents and young adults. Unlike acne vulgaris, it is pruritic, does not contain comedones, and responds to appropriate antifungal therapy rather than antibiotics. The yeast and hyphae can be seen in biopsy specimens in the widened follicular ostia along with keratinous material, and, occasionally rupture of the follicular wall may occur.