Tenemine combines tenofovir disoproxil fumarate 300 mg with emtricitabine 200 mg in one daily tablet. It is used as part of HIV treatment, and — importantly — as PrEP, taken by HIV-negative people to prevent infection. Which of those applies changes everything about how it is used.
What is Tenemine?
Tenemine is a Schedule 4 tablet listed in the South African Medicine Price Registry containing:
| Ingredient | Amount |
|---|---|
| Tenofovir disoproxil fumarate | 300 mg |
| Emtricitabine | 200 mg |
(The register spells the second ingredient “Emitricitabine” — a typographical variant of emtricitabine, not a different substance.)
Both are NRTIs — nucleoside/nucleotide reverse transcriptase inhibitors. HIV must convert its RNA into DNA to establish itself in a cell, using an enzyme called reverse transcriptase. These medicines resemble the natural building blocks that enzyme uses; when incorporated, they stop the chain being extended, and the copying fails.
The two are paired because they work at the same step in complementary ways, and the combination has a good resistance profile. This pairing — often called TDF/FTC — is one of the most-used drug combinations in the world.
It has two entirely different uses, and the distinction is not cosmetic:
As HIV treatment, it is one part of a combination regimen. It is always taken with at least one further antiretroviral from a different class — most often dolutegravir. It must never be used alone to treat HIV, because a single agent allows resistance to develop rapidly.
As PrEP (pre-exposure prophylaxis), the same tablet is taken by someone who is HIV-negative to prevent them acquiring HIV. Taken consistently, it is highly effective — well over 90% risk reduction for sexual transmission.
What is Tenemine commonly used for?
HIV treatment:
- Treating HIV-1 infection in adults and adolescents, in combination with other antiretrovirals.
- First-line and second-line regimens, depending on treatment history.
- Hepatitis B, which tenofovir also treats — relevant because HIV and hepatitis B commonly occur together.
HIV prevention:
- PrEP for people at substantial risk of HIV — including serodiscordant couples, sex workers, men who have sex with men, and anyone whose circumstances put them at ongoing risk. PrEP is available free at public health facilities in South Africa, and it does not require a partner’s involvement or knowledge.
- PEP (post-exposure prophylaxis), as part of a 28-day course started as soon as possible — and within 72 hours — after a possible exposure, whether from sex, a sexual assault, or a needlestick injury. The sooner it is started, the better it works, so this is an emergency, not a next-week matter.
The single most important safety point about PrEP: you must be confirmed HIV-negative before starting, and tested regularly while taking it. Taking TDF/FTC alone when you already have undiagnosed HIV amounts to treating HIV with two drugs instead of three, and that is how resistance develops — potentially compromising future treatment options. This is why PrEP always comes with a testing schedule.
PrEP does not protect against other sexually transmitted infections or pregnancy. Condoms still matter.
How Tenemine fits into this medicine category
| Class | Examples | How it works |
|---|---|---|
| NRTIs | Tenofovir + emtricitabine (Tenemine), lamivudine, abacavir | Block the copying of viral genetic material |
| Integrase inhibitors | Dolutegravir combinations (Acriptega) | Block HIV inserting itself into cell DNA |
| NNRTIs | Efavirenz, doravirine | Block reverse transcriptase differently |
| Protease inhibitors | Lopinavir/ritonavir | Stop new viral particles maturing |
| Hepatitis B treatment | Tenofovir-containing products (Hetemcit) | Hepatitis B, and HIV where both are present |
Tenofovir and emtricitabine form the backbone of a regimen, with a third agent from another class added on top. See the HIV and antiviral medicines hub.
What to check before using Tenemine
Get an HIV test first. Whether the plan is treatment or PrEP, this determines everything.
Tell your doctor or pharmacist if you:
- Have kidney disease or reduced kidney function. This is the main safety consideration. Tenofovir disoproxil can affect the kidneys, and kidney function must be checked before starting and monitored during treatment.
- Have hepatitis B. This matters enormously in both directions: tenofovir and emtricitabine both treat hepatitis B, and stopping them suddenly can cause a severe hepatitis flare. Anyone taking this combination should be tested for hepatitis B beforehand, and must never stop it abruptly without medical supervision.
- Have osteoporosis, low bone density, or a history of fractures. Tenofovir disoproxil can reduce bone mineral density.
- Take anti-inflammatories regularly, or other medicines affecting the kidneys.
- Are pregnant, planning pregnancy or breastfeeding. Both PrEP and treatment can be used in pregnancy, but this needs a clinician’s input.
- Take any other medicine, supplement or traditional remedy.
Practical points:
- Take it at the same time every day. Consistency is what makes both treatment and PrEP work.
- Take it with food if it causes nausea.
- For treatment, never take it alone — it is always part of a combination.
- For PrEP, understand the ramp-up. Protection takes several days of daily dosing to establish, and the timing differs by type of exposure. Follow the guidance you are given rather than assuming immediate protection.
- Keep your testing schedule — HIV testing every three months on PrEP, plus kidney function checks.
- Do not run out. Contact the clinic before your supply ends.
- Never share tablets.
Possible cautions and when to ask a pharmacist or doctor
Common effects, mostly early, are nausea, diarrhoea, headache, tiredness, dizziness, abdominal discomfort and unusual dreams. Most settle within the first weeks.
Get emergency help for:
- Deep or rapid breathing, severe muscle pain, unusual tiredness, feeling very cold, severe abdominal pain with vomiting — possible lactic acidosis, which is rare but serious.
- Yellowing of the skin or eyes, dark urine, pale stools, or persistent right-sided abdominal pain — possible liver problems, and particularly important if you have hepatitis B.
- Swelling of the face, lips or tongue, difficulty breathing, or a widespread blistering rash.
Seek prompt advice for:
- Reduced urine output, swollen ankles, unusual tiredness, or increased thirst and urination — possible kidney effects.
- Bone pain, or a fracture from a minor injury.
- Fever, swollen glands or new symptoms in the first weeks of HIV treatment — the immune system recovering can react to previously silent infections. This is treatable and is not a sign the medicine is failing.
Contact your clinic if:
- You are struggling to take it every day — for any reason. Missed doses are how resistance develops on treatment, and how protection fails on PrEP. Clinics deal with this constantly and would far rather hear about it.
- You think you may have been exposed to HIV while on PrEP, or have symptoms of a new infection — fever, rash, sore throat and swollen glands a few weeks after exposure.
- You want to stop PrEP, so it can be stopped correctly and hepatitis B considered.
- You have hepatitis B and are stopping for any reason.
Related medicine guides
Frequently asked questions
What are Tenemine tablets used for? Two things: as part of a combination regimen to treat HIV, and — for HIV-negative people — as PrEP to prevent HIV infection. It contains tenofovir disoproxil fumarate 300 mg and emtricitabine 200 mg.
Can I take it on its own to treat HIV? No. HIV treatment always uses a combination. Taking these two alone allows resistance to develop.
What is PrEP? Pre-exposure prophylaxis — this tablet taken daily by an HIV-negative person to prevent infection. Taken consistently it is highly effective, and it is available free at public health facilities in South Africa.
Do I need an HIV test first? Yes, always, and repeat testing every three months on PrEP. Taking it while unknowingly HIV-positive risks developing resistance.
Does PrEP protect against other infections? No. It prevents HIV only — not other sexually transmitted infections or pregnancy. Condoms still matter.
What if I have hepatitis B? Tell your doctor. Both ingredients also treat hepatitis B, and stopping them suddenly can cause a severe flare. Never stop abruptly.
Why do I need kidney tests? Tenofovir disoproxil can affect kidney function, so it is checked before starting and monitored during use.
What if I missed a dose? Take it as soon as you remember unless the next is nearly due; never double up. If you miss doses often, tell your clinic — for PrEP it means you may not be protected.