In a prospective, multicentre, switch study to identify the most frequently occurring nucleoside reverse transcriptase inhibitor (NRTI)-associated toxicities that cause NRTI withdrawal in virologically suppressed HIV-infected patients, among those who underwent stavudine substitution by tenofovir, 271 had hypertriglyceridemia and 193 had hypercholesterolemia. After 12 weeks of switching from stavudine to tenofovir, triglyceride and cholesterol levels showed significant de-creases, which suggests that such a switch may reverse, at least partly, stavudine-associated dyslipidaemia.