Zalcitabine

Zalcitabine (ddC) is a pyrimidine nucleoside that inhibits the replication of HIV-1. Like zidovudine, intracellular activation by triphosphorylation is catalyzed by cellular enzymes; competitive inhibition of the reverse transcriptase and chain termination result. The drug is effective as treatment for patients with HIV infection. It is available in oral formulation only and is typically prescribed in combination with zidovudine. Zalcitabine therapy is associated with a dose-dependent peripheral neuropathy that appears to occur more frequently in patients with low serum cobalamin levels and in those with a history of excessive ethanol consumption. Other reported toxicities include pancreatitis, esophageal ulceration and stomatitis, and arthralgias. Coadministration of drugs that cause either peripheral neuropathy or pancreatitis may increase the frequency of these adverse effects.