Zalcitabine adverse effects

Additional nucleoside analogues like the purine dideoxynucleosides lamivudine (3TC) and dideoxy-cytidine (ddC, zalcitabine) act in the same way as AZT. Resistance against these agents may show different patterns. They are generally less toxic than AZT. Adverse effects include diarrhoea and other gastrointestinal disturbances, headache, anxiety, restlessness and insomnia. Also hepatotoxicity can occur, probably because some of these drugs might have also some affinity for human DNA polymerases in the liver. 

Potential adverse effects are headache, dizziness, insomnia, fatigue, and gastrointestinal discomfort, although these are typically mild. Lamivudine s bioavailability increases when it is -administered with trimethoprim-sulfamethoxazole. Lamivudine and zalcitabine may inhibit the intracellular phosphorylation of one another therefore, their concurrent use should be avoided if possible. Short-term safety of lamivudine has been demonstrated for both mother and infant. 

The adverse effects of zalcitabine include peripheral neuropathy, oral ulceration and stomatitis. Additional side effects may include elevated hepatic transaminases, arthralgias, myalgias, fatigue, headache, fever and cardiomyopathy. 

LAMIVUDINE, TENOFOVIR, ZALCITABINE FOSCARNET SODIUM t adverse effects with tenofovir and possibly lamivudine and zalcitabine Uncertain possibly additive toxicity via competition for renal excretion Avoid if possible otherwise monitor FBC and renal function weekly... 

NUCLEOSIDE REVERSE TRANSCRIPTASE INHIBITORS GANCICLOVIRAfALGANCIC LOVIR 1. T adverse effects with tenofovir, zidovudine and possibly didanosine, lamivudine and zalcitabine 2. Possibly 1 efficacy of ganciclovir 1. Uncertain possibly additive toxicity. Lamivudine may compete for active tubular secretion in the kidneys 2. Uncertain L bioavailability 1. Avoid if possible otherwise monitor FBC and renal function weekly. It has been suggested that the dose of zidovudine should be halved from 600 mg to 300 mg daily. Monitor for peripheral neuropathy, particularly with zalcitabine 2. Uncertain clinical significance if in doubt, consider alternative cytomegalovirus prophylaxis... 

ZALCITABINE H2 RECEPTOR BLOCKERS -CIMETIDINE t efficacy and adverse effects of zalcitabine l excretion via inhibition of tubular secretion Clinical significance unclear. Monitor more closely... 

Adverse effects Didanosine Lamivudine Stavudine Zalcitabine Zidovudine... 

Cardiomyopathy is a rare adverse effect that has been observed in patients treated with didanosine, zidovudine, and zalcitabine (12). In a retrospective, case-control study, cardiomyopathy was 8.4 (95% Cl = 1.7, 42) times more likely to develop in children who had previously used zidovudine than in children who had never been exposed to it (13). 

Zalcitabine is a nucleoside analogue reverse transcriptase inhibitor. Because of the high incidence of nervous system adverse effects and the availability of less toxic alternatives, zalcitabine is no longer used. 

Several large-scale studies of the efficacy of combined antiretroviral treatment with zalcitabine and zidovudine in HIV-infected patients (compared with zidovudine monotherapy or a combination of zidovudine and dida-nosine) have not shown unexpected adverse effects (1-4). The most common adverse effects in patients taking zalcitabine were peripheral neuropathy and aphthous mouth ulcers. 

In vitro, stavudine had no significant effect on the intracellular activation ofzalcitabine. Both stavudine and zalcitabine have the potential to cause peripheral neuropathy and pancreatitis. Combined use of drugs causing these serious adverse effects should be closely monitored (see also NRTIs + Drugs that cause pancreatitis , p.797). US guidelines say that the combination of stavudine and zalcitabine should not be recommended at any time because of additive peripheral neuropathy. ... 

Probenecid reduces the loss of zalcitabine and zidovudine, increasing their serum levels. The combination of zalcitabine and probenecid is well tolerated, but the incidence of adverse effects appears to be greatly increased with the combination of probenecid and zidovudine. 

As a class effect NRTIs are associated with lactic acidosis and hepatic steatosis, conditions which may occur more frequently in pregnant women. The individual NRTIs have their own adverse reactions. Pancreatitis is seen with lamivudine, stavudine, di-danosine and rarely with zalcitabine while the latter three agents can also induce peripheral neuropathy. 

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