Antihypertensives decrease osteonecrosis resulting from chemotherapy. Mice treated with dexamethasone and asparaginase (Dex+ASP, red) for 6 weeks develop osteonecrosis. Mice who received quinapril in addition to dexamethasone and asparaginase (Dex+ASP+Quinapril, dark blue) developed less osteonecrosis (12/78 vs 30/78; P = .0022). In a second experiment, hydralazine given with dexamethasone and asparaginase (Dex+ASP+Hydralazine, light blue) also decreased osteonecrosis compared with chemotherapy alone (1/44 vs 20/62; P = .0035).