Tenofovir Disoproxil

Antiviral, Systemic · Nucleoside reverse transcriptase inhibitor

Indications

In combination with other antiretrovirals to treat HIV infection.

Dosage

Adults: 300 mg daily with food. Children: Not recommended.

Adverse Effects

GI upset, hyperphosphataemia, dizziness, headache, raised ALT, fatigue. Rarely, pancreatitis, rash, renal abnormalities, lactic acidosis, pruritus, arthralgia, asthenia.

Risk Factor (Pregnancy/Lactation)

Pregnancy: Risk cannot be ruled out. Lactation: Caution advised or effect undetermined. Precautions: Renal or hepatic impairment, hyperphosphataemia. Monitor renal function before treatment, every 4 weeks during first year, then every 3 months; reduce dose or interrupt therapy if serum phosphate or creatinine clearance is decreased. Risk of osteonecrosis; monitor for signs of joint pain or immobility. Reduced bone mineral density. Cirrhosis; monitor for hepatic decompensation. Caution in patients (particularly obese women) with hepatomegaly, hepatitis or other risk factors for liver disease and hepatic steatosis; monitor for lactic acidosis, discontinue therapy if occurs. Risk of lipodystrophy and metabolic abnormalities; monitor for physical signs of fat redistribution, measure fasting serum lipids and blood glucose. Monitor children exposed in utero for signs of mitochondrial…

Interactions

Nephrotoxic drugs, drugs eliminated by active tubular secretion, nucleoside analogues, atazanavir, didanosine, adefovir, tacrolimus. Triple therapy with lamivudine plus abacavir, or lamivudine plus didanosine. Protease inhibitors.

Advice to Patient

Take with or without meals in a constant manner (always with meals or always without meals). Inform prescriber immediately if there is loss of sensation/numbness/tingling in toes/fingers/feet, unrelieved abdominal discomfort, nausea, vomiting, diarrhoea, perineal itching, burning on urination, white plaques in mouth, unhealed sores, constant cough or sore throat. Take precautions to prevent spread of infection. Take sufficient amount of fluids (2-3 litres per day) to maintain hydration, unless restricted by the prescriber. Avoid highly crowded places to prevent infections. Do not get vaccinated without consulting prescriber.

Pharmacokinetics

Metabolism: Intracellular. Bioavailability: Tab: Approx. 25% (fasting); increases approx. 40% with high-fat meal. Powd: Peak serum conc are 26% lower compared to tab, but the main AUCs are similar. Half-life elimination: Serum: 17 hrs. Intracellular: 10-50 hrs. Time to peak, serum: Fasting: 36-84 mins. With high-fat meal: 96-144 mins. Excretion: Urine (70%-80%) via filtration and active secretion. After multiple oral doses (administered with food): 32% ± 10% is excreted in the urine within 24 hrs.

Brands with this active ingredient

Compiled by Healify Pharmacy from published drug references. How we compile it →

Always consult a pharmacist or doctor.