Retrovir

Zidovudine

Oral soln: Combination antiretroviral therapy (CART) for HIV-infected adults & childn. IV infusion: Short-term management of serious manifestations of HIV infection in patients w/ AIDS who are unable to take oral treatment. Do not use as monotherapy for this indication. Oral soln/IV infusion: Chemoprophylaxis in HIV +ve pregnant women (>14 wk of gestation) for prevention of maternal-foetal HIV transmission. Primary prophylaxis of HIV infection in newborn infants. Use IV only when oral treatment is not possible.

Oral soln Adult & adolescent ≥30 kg 250 or 300 mg bd in combination w/ other antiretroviral agents. Childn 9 to <30 kg 0.9 mL/kg (9 mg/kg) bd in combination w/ other antiretroviral agents. Max: 300 mg (30 mL) bd; 4 to <9 kg 1.2 mL/kg (12 mg/kg) bd in combination w/ other antiretroviral agents. Severe renal impairment; ESRD maintained on haemodialysis or peritoneal dialysis 100 mg every 6-8 hr. IV infusion Must be diluted prior to administration. Administer diluted product by slow IV infusion over a 1-hr period. Administer to patient only until oral therapy can be administered. Adult 1 or 2 mg/kg every 4 hr. Childn 80-160 mg/m² every 6 hr (320-640 mg/m² daily). Severe renal impairment 1 mg/kg tds to qds. ESRD maintained on haemodialysis or peritoneal dialysis 100 mg every 6-8 hr. Oral soln/IV infusion Prevention of maternal-foetal transmission Pregnant women (>14 wk of gestation) 500 mg daily (100 mg 5 times daily) PO until beginning of labour. During labour & delivery: 2 mg/kg IV over 1 hr, followed by continuous IV infusion at 1 mg/kg/hr until umbilical cord is clamped. Planned caesarean: Start infusion 4 hr pre-op. False labour: Stop infusion & restart oral dosing. Neonates 0.2 mL/kg (2 mg/kg) PO every 6 hr, starting w/in 12 hr after birth & continuing until 6 wk old. Unable to receive PO: 1.5 mg/kg IV infused over 30 min every 6 hr.

May be taken with or without food.

Hypersensitivity. Abnormally low neutrophil count (<0.75 x 10⁹/L) or abnormally low Hb levels (<7.5 g/dL or 4.65 mmol/L). Newborn infants w/ hyperbilirubinaemia requiring treatment other than phototherapy, or w/ increased transaminase levels of over 5 times ULN.

Residual risk of HIV transmission. Opportunistic infections & other complications of HIV infection may continue to develop. Haematological adverse reactions eg, anaemia, neutropenia, leucopenia; carefully monitor haematological parameters. Discontinue treatment in case of symptomatic hyperlactatemia & metabolic/lactic acidosis, progressive hepatomegaly, or rapidly elevating aminotransferase levels. Caution when administering in patients (particularly obese women) w/ hepatomegaly, hepatitis or other known risk factors for liver disease & hepatic steatosis. Reports of mitochondrial dysfunction in HIV -ve infants exposed in utero &/or post-natally to nucleoside analogues. Risk of lipoatrophy; regularly assess for signs of lipoatrophy during therapy. Increases in wt & in levels of blood lipids & glucose may occur during antiretroviral therapy. Increased risk of severe & potentially fatal hepatic adverse events in patients w/ chronic hepatitis B or C treated w/ CART. Risk of immune reactivation syndrome. Reports of osteonecrosis particularly in patients w/ advanced HIV disease &/or long-term exposure to CART. Avoid concomitant use w/ rifampicin or stavudine. Not recommended w/ concomitant use of ribavirin. Not recommended in patients w/ moderate to severe liver disease. Patients w/ renal impairment. Pregnancy. HIV-infected mothers should not breast-feed to avoid HIV transmission. Special care in the elderly due to age-associated changes. Oral soln: Patients w/ rare hereditary problems of fructose intolerance should not take this medicine. IV infusion: Not for IM administration. Latex allergy.

Headache; nausea. Anaemia, neutropenia, leucopenia; dizziness; vomiting, diarrhoea, abdominal pain; raised blood levels of liver enzymes & bilirubin; myalgia; malaise.

Decreased AUC w/ rifampicin. Concomitant use w/ stavudine may lead to antagonistic reactions. Increased AUC w/ probenecid. Modest increase in C_max w/ lamivudine. Altered blood levels of phenytoin. Decreased rate of metabolism w/ atovaquone. Increased AUC & decreased clearance w/ valproic acid, fluconazole or methadone. Exacerbation of anaemia w/ ribavirin. Increased risk of adverse reactions w/ nephrotoxic or myelosuppressive drugs (eg, systemic pentamidine, dapsone, pyrimethamine, co-trimoxazole, amphotericin, flucytosine, ganciclovir, interferon, vincristine, vinblastine & doxorubicin). Oral soln: Reduced absorption w/ clarithromycin tab.

Antivirals

J05AF01 - zidovudine ; Belongs to the class of nucleoside and nucleotide reverse transcriptase inhibitors. Used in the systemic treatment of viral infections.

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