Emtricitabine + Tenofovir disoproxil

Emtricitabine + Tenofovir disoproxil belongs to a group of medicines called antiretrovirals. It is used to treat HIV (human immunodeficiency virus), the virus that can cause AIDS (acquired immunodeficiency syndrome). It helps to control HIV infection so your immune system can work better.

Emtricitabine + Tenofovir disoproxil is not a cure for HIV/AIDS and only helps to decrease the amount of HIV in your body. This helps to lower your risk of getting HIV-related complications and improves your lifespan. It may also be used to prevent HIV infection in some people at high risk. It may be prescribed alone or in combination with other HIV medicines.

This medicine is best taken with food. Taking these medicines regularly at the right time greatly increases their effectiveness and reduces the chances of HIV becoming resistant to them. It is important not to miss doses and to keep taking them until your doctor tells you it is safe to stop.

Common side effects of this medicine include nausea, diarrhea, headache, trouble sleeping, rash, and dizziness. These are usually not serious but inform your doctor if they bother you or do not go away. It can also increase the risk of bone loss (osteoporosis) if you take it for a long time. Exercise regularly and take calcium and vitamin D supplements as suggested by your doctor.

Before taking it, let your doctor know if you have any liver or kidney disease or bone problems. While using it, you may need regular blood tests to check your blood counts, liver function, and kidney function. Since this medicine may cause dizziness or sleepiness, do not drive if you experience these symptoms. Pregnant or breastfeeding women should consult their doctor before using this medicine.

• HIV Infection: Used for the treatment and control of HIV-1 infection.
• Pre-Exposure Prophylaxis (PrEP): Used to prevent HIV infection in high-risk individuals.

Antiretroviral drugs

Antiretroviral (NRTI)

Tenofovir disoproxil fumarate, a diester prodrug of tenofovir, is rapidly converted to tenofovir, an acyclic nucleoside phosphonate (nucleotide) analogue of adenosine 5'-monophosphate while emtricitabine is a synthetic nucleoside analogue of cytidine. Both emtricitabine and tenofovir inhibit HIV-1 reverse transcriptase, resulting in DNA chain termination.

Emtricitabine and Tenofovir disoproxil inhibit HIV-1 reverse transcriptase enzyme, preventing the virus from making DNA. This disrupts the viral replication process and reduces the amount of virus in the body.

Adult Dose:

• HIV-1 infection & Pre-exposure Prophylaxis: 1 tablet once daily with food.
• Hepatic impairment: No dosage adjustment necessary in moderate-to-severe hepatic impairment.

Renal Dose:

• CrCl 30-49 mL/min: 1 tablet every 48 hours.
• CrCl <30 mL/min: Not recommended.
• Haemodialysis patients: Not recommended.

Take this medicine in the dose and duration as advised by your doctor. Swallow it as a whole. Do not chew, crush or break it. Emtricitabine + Tenofovir disoproxil is to be taken with food. Taking it with food increases absorption of the medicine into the body.

If you miss a dose of Emtricitabine + Tenofovir disoproxil, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose. Do not double the dose. Skipping doses increases the risk of treatment failure.

Common Side Effects:

• Diarrhea
• Dizziness
• Fatigue
• Headache
• Nausea
• Rash

Other Side Effects:

• Trouble sleeping
• Osteoporosis (bone loss with long-term use)
• Weight gain
• Muscle pain

Precautions:

• Emtricitabine + Tenofovir disoproxil may decrease alertness, affect your vision or make you feel sleepy and dizzy. Do not drive if these symptoms occur.
• Take with food, as this increases the absorption of the medicine into the body.
• Skipping doses increases the risk of treatment failure. Make sure that you take all your doses at the correct time.
• Always practice safe sex while taking this medicine.
• Do not share needles or personal items that can have blood or body fluids on them.
• It may cause weakening of your bones. Exercise regularly and take calcium and vitamin D supplements as suggested by your doctor.
• Let your doctor know if you have any liver or kidney disease or bone problems.
• Pregnant or breastfeeding women should consult their doctor before using this medicine.

Contraindications:

• Lactation
• Not to be used for treatment of chronic hepatitis B virus (HBV) infection
• Hypersensitivity to emtricitabine or tenofovir

Drug Interactions:

• Atazanavir: Decreased atazanavir concentration with tenofovir unless also co-administered with ritonavir.
• Drugs eliminated by active tubular secretion: Increased serum concentration of both tenofovir and emtricitabine or co-administered drug.
• Nephrotoxic agents (aminoglycosides, amphotericin B, foscarnet, ganciclovir, pentamidine, vancomycin, cidofovir or interleukin-2): Increased risk of renal impairment; avoid if possible.
• Didanosine: Increased didanosine levels and thereby increasing risk of pancreatitis and peripheral neuropathy; avoid concurrent use.
• Lamivudine: Do not use emtricitabine with lamivudine due to similar resistance profile.
• β-interferon: Increased risk of lactic acidosis.

Food Interactions: Taking with food increases absorption of the medicine. It is not known whether it is safe to consume alcohol; consult your doctor.

Use in Pregnancy: Emtricitabine + Tenofovir disoproxil is generally considered safe to use during pregnancy. Animal studies have shown low or no adverse effects to the developing baby; however, there are limited human studies. Use under medical supervision.

Use in Lactation: Emtricitabine + Tenofovir disoproxil is probably safe to use during breastfeeding. Limited human data suggests that the drug does not represent any significant risk to the baby. However, as HIV infection can be transmitted through breast milk, breastfeeding should be avoided. Consult your doctor.

Pediatric Use: Safety and effectiveness in pediatric patients have not been established. Use under medical supervision.

Geriatric Use: Use with caution in elderly patients. As kidney function may decrease with age, regular monitoring of kidney function is recommended.

Renal Impairment: Use with caution. CrCl 30-49 mL/min: 1 tablet every 48 hours. CrCl <30 mL/min: Not recommended. Not recommended for dialysis patients. Regular monitoring of kidney function is recommended.

Hepatic Impairment: Probably safe in patients with liver disease. Limited data available suggests dose adjustment may not be needed. Consult your doctor.

Overdose: Limited information is available on overdose. Overdose may cause gastrointestinal discomfort, dizziness, fatigue. In case of overdose, seek immediate medical attention and symptomatic treatment.

Storage: Store below 30°C, away from light and moisture. Keep out of reach of children.

Emtricitabine + Tenofovir disoproxil