Tenvira (Tenofovir Disoproxil Fumarate)
Therapeutic Group : Antiviral
Recommended dose in adults 18 years of age or older for the treatment of chronic hepatitis B infection: The recommended dose is 300 mg once daily with or without food. However, it is generally recommended to be taken with a meal to improve bioavailability.
Usual adult dose for HIV infection: 300 mg orally once a day.
Patients with renal impairment: No dosage adjustment is necessary for patients with mild renal impairment (creatinine clearance 50-80 mL/min). Since tenofovir is principally eliminated by the kidney, in the case of severe renal impairment, including cases of acute renal failure and Fanconi syndrome- dosage adjustment is required in all patients with creatinine clearance <50 ml/min, as detailed in table.
|Recommended dose||300 mg every 24 hours||300 mg every 48 hours||300 mg every 72 to 96 hours||Every 7 days or after approximately 12 hours of dialysis|
In hepatic impairment: No dose adjustment is required in patients with hepatic impairment.
Lactic acidosis/severe hepatomegaly with steatosis: Though the risk of occurrence of lactic acidosis is low for tenofovir, treatment should be suspended in any patient who develops lactic acidosis or hepatotoxicity.
Exacerbation of hepatitis after discontinuation of treatment: Discontinuation of Tenofovir therapy may be associated with severe acute exacerbations of hepatitis. Monitor liver function tests every 3 months, and viral and serological markers for hepatitis B every 3-6 months. Discontinue if deterioration in liver function, hepatic steatosis, progressive hepatomegaly or unexplained lactic acidosis. Recurrent hepatitis may occur on discontinuation.
Lactation: It is not known whether it is excreted in human milk. Mothers should be instructed not to breast-feed if they are receiving Tenofovir.
Pediatric use: The use of Tenofovir is not recommended for pediatric patients.
Geriatric use: In general, dose selection for the elderly patient should be cautious, keeping in mind the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.