Zidovudine Flucytosine

Zidovudine should be used cautiously with any other agent that causes bone marrow suppression, such as interferon-a, trimethoprim-sulfamethoxazole, dap-sone, foscarnet, flucytosine, ganciclovir, and valganci-clovir. Probenecid and interferon-p inhibit the elimination of zidovudine therefore, a dosage reduction of zidovudine is necessary when the drugs are administered concurrently. Ribavirin inhibits the phosphorylation reactions that activate zidovudine, and zidovudine similarly inhibits the activation of stavudine thus, the coadministration of zidovudine with ribavirin or stavudine is contraindicated. 

Drug Interactions Zidovudine Probenecid Imipenem-cilastatin Dapsone Pentamidine Flucytosine Vincristine Vinblastine Adriamycin Amphotericin B TMP-SMX Other nucleoside analogues... 

Drug Interactions Antineoplastlc agents Corticosteroids and corticotropin Cyclosporine-A Digitalis glycosides Flucytosine Imidazoles Leukocyte transfusions Nephrotoxic medications Skeletal muscle relaxants Zidovudine... 

FLUCYTOSINE ANTIVIRALS-ZIDOVUDINE Possibly t adverse effects with zidovudine Additive toxicity Avoid if possible otherwise monitor FBC and renal function (weekly). 1 doses as necessary... 

Zidovudine is rapidly absorbed from the G1 tract with peak serum concentrations occurring within 30 to 90 minutes. It binds to plasma proteins to the extent of 35 to 40%. Zidovudine is rapidly metabolized in the liver to the inactive 3 -azido-3 -deoxy-5 -0-beta-D-glucopyranuronosylthymi-dine (GAZT), which has an apparent elimination half-life of 1 hour. Zidovudine undergoes glomerular filtration and active tubular secretion. Coadministration of zidovudine with agents such as dapsone, pentamidine, amphotericin B, flucytosine, vincristine, vinblastine, adriamycin, and interferon with potential to cause nephrotoxicity or cytotoxicity to hematopoietic elements, enhance its risk of adverse effects. Probenecid will inhibit the renal excretion of zidovudine. 

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