In this double-blind, randomized trial, we compared the clinical efficacy of intralesional vinblastine (VNB) and 3% sodium tetradecyl sulfate (STS) in the treatment of oral Kaposi's sarcoma (OKS). Subjects with OKS were randomly assigned to receive a single intralesional injection of either VNB or STS, at a standard dose (0.2 mg/cm(2)). Differences were evaluated by the Mann-Whitney U and Fisher's exact tests. Sixteen HIV-infected patients were included, eight received VNB and eight received STS; clinical response was evaluated at days 7, 14, and 28 following treatment. Tumor size reduction was 0.68 and 0.61 cm in the VNB and STS groups, respectively (P=0.80). Two VNB patients had complete or partial response whereas four STS subjects had partial responses (P=0.61). Patients in both groups experienced minimal toxicity. We conclude that intralesional vinblastine or STS are adequate for the management of OKS. The benefits of STS are its low cost and ease of use.