Etravirine (Intelence)

How does it work?

Intelence tablets contain the active ingredient etravirine, which is a type of medicine called a non-nucleoside reverse transcriptase inhibitor. It is used in the treatment of HIV (human immunodeficiency virus) infection.

AIDS (acquired immune deficiency syndrome) is caused by infection with HIV. This virus invades cells of the immune system, particularly the white blood cells known as CD4 T-helper lymphocytes. These cells normally work to activate other cells in the immune system to fight infection. Since HIV kills CD4 T-helper cells, over time the body becomes less able to fight the virus or subsequent infections.

Once the virus is inside the CD4 T-cell it multiplies. Part of the process of viral multiplication involves the conversion of the virus genetic material, RNA, into DNA. This is achieved by a compound essential to the virus, called reverse transcriptase. Reverse transcriptase is a compound known as an enzyme. Etravirine works by blocking the action of this enzyme, thereby interfering with the conversion of viral RNA into DNA. This stops the virus from multiplying.

There is no cure for HIV, but etravirine is one of a number of medications that lowers the amount of virus in the body (viral load) and slows the progression of the disease from HIV to AIDS. Etravirine is used in combination with other anti-HIV drugs that attack the HIV virus in different ways. This minimises the virus's ability to replicate and multiply, and helps prevent it becoming resistant to treatment.

What is it used for?

  • HIV infection.


  • This medicine should be taken after a meal, as food increases the absorption of the medicine into the body. If you take the tablets on an empty stomach only half the amount of medicine is absorbed.
  • Treatment of HIV infection with anti-HIV medicines such as this one does not reduce the risk of transmitting the virus to other people through sexual contact or blood contamination. You should continue to use condoms to prevent transmitting the virus to your sexual partner.
  • The HIV virus is very good at becoming resistant to anti-HIV medicines. For this reason it is very important that you carefully follow your doctor's instructions for taking your anti-HIV medicines, in order to maintain effective levels of the medicines in your blood. If the blood levels drop, the virus will be given more chance to replicate and develop resistance to the drugs. Skipping even a few doses increases the risk of treatment failure, so you should try to ensure that you take all your doses at the correct time, and that you visit your doctor for repeat prescriptions before you run out of medicine.
  • If you forget to take a dose of this medicine and it is less than six hours late, you should take that dose after a meal as soon as possible and then take your next dose at the normal time. If you are more than six hours late taking a dose, you should not take the missed dose and continue taking your tablets at the normal time.
  • A rash is the most common side effect associated with this medicine. It is most likely to occur in the second week after starting treatment and is more likely in women. The rash is usually mild to moderate and usually gets better on its own in a couple of weeks without stopping treatment. However, on rare occasions the rash may get worse and serious blistering or peeling skin reactions (eg Stevens-Johnson syndrome, erythema multiforme) may occur. For this reason, you should consult your doctor if you get a skin rash that is getting worse, or sores inside your mouth while you are taking this medicine, because you may need to stop treatment.
  • Combination antiretroviral therapy has been associated with a redistribution of body fat (lipodystrophy) in people with HIV. The long-term consequences of this are currently unknown, however your doctor may wish to monitor your body fat, and the levels of lipids (eg cholesterol) and sugar (glucose) in your blood, and may prescribe additional medicines for any lipid disorders that occur during treatment with this medicine. Contact your doctor if you notice any changes in your body fat during treatment with your HIV medicines.
  • Some people being treated with combination antiretroviral therapy may develop a bone condition called osteonecrosis. This condition is caused by loss of blood supply to a bone, causing death of the bone tissue. The risk of the condition is thought to be increased by corticosteroid use, alcohol consumption, severe immunosuppression, higher body mass index, advanced HIV disease and long-term use of antiretroviral medicines. If you notice any joint stiffness, aches and pains (especially of the hip, knee and shoulder) or difficulty in movement while using this medicine, you should tell your doctor so this can be investigated.
  • If you have advanced HIV and a history of opportunistic infections such as pneumocystis carinii pneumonia (PCP), severe fungal infections or cytomegalovirus (CMV), you may experience signs and symptoms of inflammation from previous infections soon after you start combination anti-HIV treatment. It is believed that these symptoms are due to an improvement in the body’s immune response, which enables the body to fight infections that may have been present with no obvious symptoms. You should tell your doctor immediately if you experience any signs or symptoms of infection, such as inflammation or high temperature, after starting treatment with this medicine.
  • You should store your Intelence tablets in the container in which they were originally dispensed and not transfer them to another container. This is because the original container contains a desiccant that stops the tablets absorbing moisture. Do not remove the desiccant pouches and keep the bottle tightly closed.

Use with caution in

  • People over 65 years of age.
  • Liver disease, particularly hepatitis B or C.
  • Moderately decreased liver function.
  • People with a history of severe skin reactions to other non-nucleoside reverse transcriptase inhibitors, eg efavirenz or nevirapine.

Not to be used in

  • Severely decreased liver function.
  • Pregnancy.
  • Breastfeeding.
  • This medicine has not been studied in children and adolescents under 18 years of age. It is not recommended for this age group.
  • Intelence tablets contain lactose and are unsuitable for people with the rare hereditary disorders of galactose intolerance, Lapp lactase deficiency or glucose/galactose malabsorption syndrome.

This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.

If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

Pregnancy and breastfeeding

Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

  • The safety of this medicine for use during pregnancy has not been investigated. It should not be used during pregnancy unless your doctor considers that the potential benefits outweigh the potential risks to the developing baby. Seek medical advice from your doctor.
  • It is not known if this medicine passes into breast milk. Mothers who need to take this medicine should not breastfeed their infants.
  • It is recommended that women infected with the HIV virus should not breastfeed their infants under any circumstances, and regardless of their treatment, in order to avoid passing the virus to the baby via their breast milk. Seek further medical advice from your doctor.

Side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect.

Very common (affect more than 1 in 10 people)

  • Rash (see warning above).
  • Diarrhoea.
  • Nausea.

Common (affect between 1 in 10 and 1 in 100 people)

  • Decrease in the number of red blood cells or platelets in the blood (anaemia or thrombocytopenia).
  • Disorder of the peripheral nerves causing weakness, tingling and numbness (peripheral neuropathy). Consult your doctor if you experience these types of symptoms.
  • Headache.
  • Disturbances of the gut such as heartburn, vomiting, nausea, abdominal pain and wind.
  • Kidney problems.
  • Difficulty in sleeping (insomnia).
  • Fatigue.
  • High blood pressure.
  • Anxiety.
  • Increased level of cholesterol or triglycerides in the blood.
  • Increased blood sugar level and diabetes.

Uncommon (affect between 1 in 100 and 1 in 1000 people)

  • Blurred vision.
  • Sleep disturbances, such as abnormal dreams, nightmares.
  • Confusion or memory loss.
  • Sleepiness.
  • Liver problems. Symptoms that may suggest a liver problem include persistent nausea and vomiting, abdominal pain, or the development of jaundice (a yellow colouring to the skin and the whites of the eyes). Consult your doctor if you experience any of these symptoms.
  • Abnormal enlargement of breasts in men (gynaecomastia).
  • Dry mouth or inflammation of the mouth.
  • Increased sweating.
  • Inflammation of the pancreas (pancreatitis).
  • Convulsions.
  • Problems with the heart such as heart attack, angina and irregular heart beat.

The side effects listed above may not include all of the side effects reported by the medicine's manufacturer.

For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

How can this medicine affect other medicines?

It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to ensure that the combination is safe.

Etravirine is not recommended for use in combination with the following anti-HIV medicines:

  • efavirenz
  • indinavir
  • nelfinavir
  • nevirapine
  • tipranavir/ritonavir.

The following medicines may decrease the amount of etravirine in the blood. This could make etravirine less effective against the virus, and could also allow the virus to become resistant to the medicine:

  • carbamazepine (not recommended in combination with etravirine)
  • dexamethasone tablets and injections
  • phenobarbital (not recommended in combination with etravirine)
  • phenytoin (not recommended in combination with etravirine)
  • rifabutin (etravirine may also decrease the blood level of rifabutin)
  • rifampicin (not recommended in combination with etravirine)
  • the herbal remedy St John's wort, Hypericum perforatum (not recommended in combination with etravirine).

Etravirine may decrease the blood levels of the following medicines and could therefore make these medicines less effective. Your doctor may need to do extra monitoring or adjust your doses if you are taking any of these medicines with etravirine:

  • immunosuppressant medicines, ciclosporin, sirolimus and tacrolimus
  • medicines for irregular heartbeats (anti-arrhythmic medicines), such as amiodarone, disopyramide, flecainide, mexilitine, propafenone, quinidine
  • phosphodiesterase type 5 inhibitors for impotence, eg sildenafil, tadalafil and vardenafil
  • statin medicines used to treat high cholesterol levels, such as atorvastatin, rosuvastatin, or simvastatin. If you are taking a statin in combination with etravirine, your cholesterol levels should be regularly monitored to make sure the statin is still producing an effect. Your doctor may need to adjust your statin dose. Pravastatin is not expected to be affected by etravirine.

Etravirine may increase the blood level of digoxin. If etravirine is used in combination with digoxin it is recommended that the blood level of digoxin is monitored.

Etravirine may increase the blood level of diazepam. As this could increase the risk of diazepam side effects, alternative medicines to diazepam are recommended.

Etravirine may increase the blood level of the anti-blood-clotting (anticoagulant) medicine, warfarin. If you are taking warfarin with this medicine, your blood-clotting time (INR) should be monitored.

Etravirine may make the antibiotic clarithromycin less effective at treating infections caused by Mycobacterium avium complex (MAC). It is recommended that other antibiotics are used to treat this infection in people taking etravirine.

Other medicines containing the same active ingredient

There are currently no other medicines available in the UK that contain etravirine as the active ingredient.