Before using this medication tell your doctor if; you are allergic to any ingredient contained within Tenvir 300mg Tablet, you have other allergies, you have kidney/ liver/ disorders, you have both HIV and HBV infections, you have difficulty swallowing your tablets, you are already taking other medications, you are pregnant, or are planning to become pregnant or are breastfeeding a baby. The dosage for this medication is determined by the doctor based on your age, medical history and current condition. The usual dose in adults for HIV infection is about 300 mg, to be taken orally once daily. http://www.moderntimes-helplinepharma.com/tenvir-tenofovir-fumarate-tablets/