Background: Hundreds of thousands of cases of cutaneous leishmaniasis occur each year worldwide. Available therapies are parenteral, moderately toxic, and costly.
Objective: To determine the efficacy of and tolerance for oral allopurinol as monotherapy for cutaneous leishmaniasis.
Design: Randomized, controlled trial.
Setting: Outpatient clinics in 11 regions of Colombia in which cutaneous leishmaniasis is endemic.
Patients: 187 otherwise healthy adults with cutaneous leishmaniasis. Eighty-four percent of patients were infected with or were from regions with Leishmania panamensis; 16% were infected or were from regions with L. braziliensis.
Intervention: Patients were randomly assigned to one of three treatment groups. The first group received allopurinol, three 100-mg tablets four times daily (20 mg/kg of body weight per day) for 28 days. The second group received three placebo tablets four times daily for 28 days. The third group received Glucantime, 20 mg of intramuscular antimony/kg per day for 20 days.
Measurement: Complete cure was defined as complete clinical reepithelialization of all lesions at 3 months and no relapse during 12 months of follow-up.
Results: Of 182 patients whose data could be analyzed, 157 (86%) were evaluated. In the allopurinol group, 18 of 55 (33% [95% CI, 21% to 47%]) patients were cured; in the placebo group, 17 of 46 patients (37% [CI, 23% to 52%]) were cured (difference, 4% [CI, −14% to 22%]; P = 0.68); and in the Glucantime group, 52 of 56 patients (93% [CI, 83% to 98%]) were cured (P < 0.001 compared with the allopurinol and placebo groups combined). In most cases, therapy was considered to have failed because the lesion did not reepithelialize by 1.5 months after the end of therapy. Three cases of relapse (two in the allopurinol group and one in the placebo group) at the nasal mucosa (mucosal leishmaniasis) had occurred by the end of 12 months of follow-up.
Conclusions: Allopurinol monotherapy has no effect on Colombian cutaneous disease primarily caused by L. panamensis and therefore is unlikely to be effective against cutaneous leishmaniasis in other endemic regions.