Table of Contents
- 1 TENOFOVIR
- 1.1 Overview and uses
- 1.2 Brand names of Tenofovir
- 1.3 Brands containing Tenofovir with other medicines
- 1.4 Pharmacological classification
- 1.5 Indication (used for)
- 1.6 Dosage
- 1.7 Dosage form
- 1.8 Overdosage
- 1.9 Pregnancy
- 1.10 Unwanted or side effects
- 1.11 Warnings and precautions before using Tenofovir
- 1.12 Interactions
- 1.13 Important information on anti-HIV and anti-AIDS medicines
Overview and uses
Tenofovir is a medicine used for HIV treatment. It is available only as a prescription medicine. Tenofovir is prescribed by a doctor in combination with other medicines for HIV treatment. This is done to increase the therapeutic efficacy of the medicines used in the treatment of HIV. Also, combination therapy reduces the risk of the virus getting resistant to any one particular medicine.
Tenofovir does not cure HIV, but it slows down the progression of HIV within the body. HIV destroys CD4+ T Lymphocytes – a type of white blood cells (WBC) that gives immunity to the body. In other words, these cells protect the body against the infections or illness caused by various organisms like bacteria, viruses and other germs. Thus, one may conclude that HIV infection, if left untreated, may make the body susceptible to these infections/illness.
Brand names of Tenofovir
Brands containing Tenofovir with other medicines
- ATRIPLA contains Tenofovir with Emtricitabine and Efavirenz.
- COMPLERA contains Tenofovir with Emtricitabine and Rilpivirine.
- GENVOYA contains Tenofovir with Elvitegravir, Cobicistat, and Emtricitabine.
- TRUVADA contains Tenofovir with Emtricitabine.
- ODEFSEY contains Tenofovir with Emtricitabine and Rilpivirine.
- STRIBILD contains Tenofovir with Elvitegravir, Cobicistat, and Emtricitabine.
Nucleotide reverse transcriptase inhibitor antiretroviral drug
Indication (used for)
- For the treatment of HIV-1 infections in adults and children with 2 years or older than 2 years of age, in combination with other anti-HIV medicines.
- For chronic hepatitis B in adults.
- Mechanism of action: Tenofovir competitively inhibits viral reverse transcriptase and gets incorporated into viral DNA to cause chain termination.
- Adult Dose:
- For the treatment of HIV-1 and chronic hepatitis B, the dose of Tenofovir is 300 mg once a day.
- For those adults with difficulty in swallowing tablets, Tenofovir powder form is available by the brand name Viread. For such cases, 7.5 scoops should be taken which is provided along with the package.
- The pediatric dose for patients with age of 2 years or more but less than 18 years:
- 8 mg/kg once a day as tablets or oral powder.
- The dose of Tenofovir (Viread) oral powder based on body weight for children with age 2 years or more:
- 10 kg or more but less than 12 kg body weight – 2 scoops of powder once a day.
- 12 kg or more but less than 14 kg body weight – 2.5 scoops of powder once a day.
- 14 kg or more but less than 17 kg body weight – 3 scoops of powder once a day.
- 17 kg or more but less than 19 kg body weight – 3.5 scoops of powder once a day.
- 19 kg or more but less than 22 kg body weight – 4 scoops of powder once a day.
- 22 kg or more but less than 24 kg body weight – 4.5 scoops of powder once a day.
- 24 kg or more but less than 27 kg body weight – 5 scoops of powder once a day.
- 27 kg or more but less than 29 kg body weight – 5.5 scoops of powder once a day.
- 29 kg or more but less than 32 kg body weight – 6 scoops of powder once a day.
- 32 kg or more but less than 34 kg body weight – 6.5 scoops of powder once a day.
- 34 kg or more but less than 35 kg body weight – 7 scoops of powder once a day.
- 35 kg or more body weight – 7.5 scoops of powder once a day.
- The dose of Tenofovir tablets for children with age 2 years or more of age and 17 kg or more of body weight:
- 17 kg or more but less than 22 kg – 150 mg once a day.
- 22 kg or more but less than 28 kg – 200 mg once a day.
- 28 kg or more but less than 35 kg – 250 mg once a day.
- 35 kg or more – 300 mg once a day.
- RENAL DOSE ADJUSTMENTS: a regular dose of 300 mg is maintained but dosing interval (time between two consecutive doses) is increased.
- Creatinine clearance equal to or more than 50 ml/min:
- 300 mg every 24 hours.
- Creatinine clearance equal to or more than 30 ml/min but less than 50 ml/min:
- 300 mg every 48 hours.
- Creatinine clearance equal to or more than 10 ml/min but less than 30 ml/min:
- 300 mg every 72 hours or 96 hours.
- If the patient is on hemodialysis:
- 300 mg every 7 days or after a total of 12 hours of dialysis.
- Creatinine clearance equal to or more than 50 ml/min:
The dose should be administered after hemodialysis on the days of dialysis at the same time when the dose is administered on nondialysis days.
Available as tablets in the strength of 150 mg, 200 mg, 250 mg
- Standard supportive treatment should be applied as and when necessary.
- Tenofovir can be removed by hemodialysis.
Category B, which means that Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.
Unwanted or side effects
- Major side effects observed are cough, chest pain, tightness in chest, troubled breathing and fever or chills are common. Diarrhea, abdominal (tummy) discomfort, muscle cramp, and weakness are rarely observed.
- Consult your doctor as soon as possible.
- Back pain and skin rash, though more common, but are not serious in nature.
- Ask your pharmacist to recommend a suitable medicine and consult your doctor.
- Lactic acidosis and severe hepatomegaly with steatosis.
- feeling or being sick, abdominal pain (tummy) pain, loss of appetite, loss of weight, feeling dizzy and fast or gasping breathing, diarrhea, sleepiness, tiredness or weakness, nausea and vomiting, pain in upper right portion of the abdomen, rash, weight loss, yellowing of the skin and whites of the eye are some of the symptoms of the above-mentioned condition. Consult your doctor as soon as possible.
- Exacerbation of hepatitis after discontinuation of therapy.
- New onset or worsening of renal impairment.
- A decrease in bone mineral density.
- Fat redistribution or accumulation of body fat including central obesity, Dorso-cervical fat enlargement (buffalo hump), peripheral wasting, facial wasting, breast enlargement and “cushingoid appearance” have been observed in patients receiving anti-HIV therapy.
- Immune reconstitution syndrome: during the initial phase of the treatment, patients whose immune systems respond may develop an inflammatory response to opportunistic infections, which may necessitate further evaluation and treatment. Autoimmune disorders have also been reported to occur in some people at any time after the initiation of the treatment.
Warnings and precautions before using Tenofovir
- Tenofovir should be used with caution in patients with pre-existing renal disease.
- Long time use of Tenofovir is associated with a small decline in Creatinine clearance.
- Tenofovir increases the activity (AUC) of Didanosine and hence, should not be used together.
- Suppression of CD4+ cells was observed in patients receiving Tenofovir and Didanosine.
- If concomitant use of both the medicines is essential than the dose of Didanosine should be reduced to 250 mg for an adult patient with 60 kg or more body weight. Dose adjustment data for the pediatric patient and adult patient with less than 60 kg body weight are not available.
- Atazanavir increases Tenofovir concentrations.
- Tenofovir decreases the activity (AUC and Cmin) of Atazanavir.
- Atazanavir without Ritonavir should not be co-administered with Tenofovir. Atazanavir 300 mg and Ritonavir 100 mg should be given along with Tenofovir.
- Lopinavir and Ritonavir increase the activity (AUC) of Tenofovir. Concomitant use of these drugs should be done with caution and under strict monitoring.
- Tenofovir should not be co-administered with Adefovir (HEPSERA) for the treatment of chronic hepatitis B.
- Ibuprofen, Amphotericin B, Aspirin, Magnesium salicylate, Salicylamide, Zoledronic acid, Ketoprofen, Amikacin, Naproxen, Salsalate, Diatrizoate, Flurbiprofen, Mesalamine, Leflunomide, Pamidronate, Choline salicylate, Diclofenac, Tacrolimus, Phenyl salicylate, Sulfasalazine, Sodium salicylate, Botulism immuno globulin, Bacitracin, Balasalazide, Tobramycin, valdecoxib, olsalazine, lomitapide, ibandronate, gentamicin, cisplatin, diclofenac, sulindac, colistimethate, capreomycin, iothalamate, celecoxib, cyclosporine, iodipamide, diflunisal, oxaprozin, deferasirox, diflunisal, etidronate, Lithium, Tacrolimus, Deferasirox, Piroxicam, Fenoprofen, Foscarnet, methotrexate, kanamycin, tobramycin, gallium nitrate, cyclosporine, ioxagalate, etidronate, etodolac, indomethacin, deferasirox, Mipomersen, Ketorolac, Ketoprofen, Etodolac, Vancomycin, Meclofenamate, Meloxicam, mefenamic acid, methoxyflurane, neomycin, nabumetone, phenylbutazone, piroxicam, pentamidine, Zoledronic, Rofecoxib, Temsirolimus, Indomethacin, Tolmetin, zoledronic acid, iodixanol, iohexol, iopamidol, iopromide, iothalamate, ioversol and ioxilan are some of the medicines that should be avoided with Tenofovir as these may worsen the renal impairment.
Drug-food interactions of Tenofovir
- Can be taken regardless of food intake.
Important information on anti-HIV and anti-AIDS medicines
Benefits of taking your anti-HIV medicines regularly
- Sustained viral suppression.
- Reduced risk of resistance.
- Reduced risk of treatment failure.
- Improved quality of life and overall health.
- Reduced risk of HIV transmission.
Getting the most from your treatment
- Precisely follow every advice given to you by your doctor and pharmacist regarding your medications. Take your dose regularly without missing out a single one.
- Make all the necessary changes in your lifestyle and eating/food habits as advised by your doctor and pharmacist. This may include quitting smoking, alcohol, other substances of abuse, taking up exercise and some/many others that your doctor finds it best in your interest.
- Do not make any changes in your dose unless suggested/recommended by your doctor.
- Keep your regular appointments with your doctor so that the progress can be monitored. This may involve blood tests and other tests that a doctor finds necessary.
- Consult your doctor if you develop an infection or an allergy after you start the treatment.
- Consult your doctor if you feel low or even depressed. This is common especially after diagnosis and during the early stages of treatment.
- Some people who have taken anti-HIV medicines for a long period of time may develop Osteonecrosis – a condition where bone tissue dies due to a reduced blood supply. This causes joint pain, stiffness, and difficulty in movement. Consult your doctor if you if you notice any of these symptoms.
- If you are going to take any operation/surgery or dental treatment, tell the doctor who is going to carry out operation/surgery or dental procedure about all the medicines that you are taking. If possible, carry your containers with you to the doctor even if it is empty.
- If you buy any medicines, supplements including your vitamin supplements, herbal medicines or even the medicines that do not require a prescription, check with your pharmacist whether they can be taken along with your anti-HIV medicines or not.
- Treatment of HIV is life-long. Continue taking your anti-HIV medicines even if you feel well. This should be done to keep your immune system healthy.
Forgot to take your medicine?
- Forgetting a dose/frequent missed out doses may lead to viral resistance or treatment failure.
- If you forget to take a dose, take it immediately as soon as you remember unless it’s almost the time for your next dose.
- Do not take two doses at the same time to make up for the missed out dose.
- If you are forgetting/missing your dose frequently or very often, try using pill boxes that are available as weekly or monthly dose boxes. Alternatively, you can also try posting reminder notes on places like doors of refrigerator, wardrobe, bathroom, side tables of your bed, above or below switchboards etc. You can also set a reminder on your cell phone.
- If possible, ask your family members and friends to remind you of your dose.
Note: The sole purpose of every information shared in this article is to bring awareness. Do not use this information as a piece of medical advice or prescription advice or as a tool for the treatment, diagnosis or prevention of the disease.