Twenty-five HIV-infected patients underwent hyperbaric oxygen therapy to determine the treatment's effectiveness in relieving the debilitating fatigue associated with HIV/AIDS and its effect on immunologic function. Patients were treated with 100% oxygen at two atmospheres of absolute pressure three times per week for two months, then two times per week on an ongoing basis. Laboratory markers were assessed monthly. All patients experienced relief of debilitating fatigue within one month of hyperbaric oxygen therapy. It was concluded that hyperbaric oxygen therapy is an effective adjunctive treatment in the medical management of HIV/AIDS. Laboratory markers, clinical significance, nursing implications, and cost-effectiveness of hyperbaric oxygen therapy are discussed.