Tenofovir

Tenofovir disoproxil is a type of medicine known as an antiretroviral drug, which is used to treat HIV and chronic hepatitis B. HIV is a sexually transmitted illness that eventually progresses to Acquired Immunodeficiency Syndrome. Chronic hepatitis B is a prolonged viral infection caused by the hepatitis B virus. It is a nucleotide reverse transcriptase inhibitor that interferes with the normal function of enzymes required for viral generation. It successfully alleviates symptoms associated with HIV and chronic hepatitis B infection. It was first authorized in 2001.

BRAND NAMES:

Atripla: It is the combination of efavirenz, emtrcitibine, and tenofovir. It is available in the form of tablets used to treat HIV-1 infection.

Complera: It is a combination of emtricitabine, rilpivirine, and tenofovir. It is available in the form of tablets used to treat a complete regimen for the treatment of HIV-1 infection.

MECHANISM OF ACTION:

Tenofovir diphosphate inhibits HIV-1 reverse transcriptase and Hepatitis B polymerase by direct binding competition with the natural DNA substrate and incorporation into DNA, resulting in viral DNA chain termination.

PHARMACOKINETICS:

Absorption: Tenofovir oral dosing resulted in a peak plasma time of 1 hour while fasting and 2 hours after meal consumption. Tenofovir has a bioavailability of 25%, which climbs to 40% following a high-fat diet.

Distribution: The volume of distribution of tenofovir at steady-state is 1.3 L/kg and 1.2 L/kg.

Metabolism: Tenofovir bisoprolol fumarate is quickly converted to tenofovir, which is then metabolized intracellularly to the active metabolite tenofovir diphosphate, which inhibits HIV-1 reverse transcriptase and ends the developing DNA chain. Tenofovir is not metabolized by any cytochrome P450.

Excretion:Tenofovir is excreted through urine.

PHARMACODYNAMICS:

This medication reduces viral DNA chain elongation in HIV-1 and hepatitis B infections by inhibiting enzymes required for host cell infection and viral replication.

DOSAGE AND ADMINISTRATION:

Tenofovir is available as a tablet to be taken orally. Typically, the pill is taken once a day, with or without meals. The powder is typically consumed with meals once a day. It is available as tablets with strengths of 150mg, 200mg, 250mg, and 300mg.

DRUG INTERACTIONS:

Drug interactions with tenofovir may include