Your doctor will want to check your progress at regular visits, especially during the first few weeks that you take this medicine. Blood tests may be needed to check for any unwanted effects.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or non-prescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
You should not use any of the following medicines while you are taking efavirenz, emtricitabine, and tenofovir combination:
- Adefovir (Hepsera®).
- Anti-HIV medicines that contain efavirenz, emtricitabine, or tenofovir (Complera®, Emtriva®, Sustiva®, Truvada®, Viread®).
- Bepridil (Vascor®).
- Cisapride (Propulsid®).
- Ergotamine medicines (such as dihydroergotamine, ergonovine, ergotamine, methylergonovine, Cafergot®, Ergomar®, Wigraine®).
- Lamivudine-containing medicines (Combivir®, Epivir®, Epivir-HBV®, Epzicom®, Trizivir®).
- Midazolam (Versed®).
- Pimozide (Orap®).
- St. John's wort.
- Triazolam (Halcion®).
- Voriconazole (Vfend®).
Two rare but serious reactions to this medicine are lactic acidosis (too much acid in the blood) and liver toxicity, including an enlarged liver. These are more common if you are female, very overweight (obese), or have been taking anti-HIV medicines for a long time. Call your doctor right away if you have abdominal or stomach discomfort, cramping, nausea, vomiting, diarrhea, or a decreased appetite, muscle cramping or pain, unusual tiredness or weakness, trouble breathing, or yellow skin or eyes.
This medicine may increase your risk of having serious mental or behavioral problems. Tell your doctor if you develop mood changes, strange thoughts, or any unusual behavior while you are using this medicine.
Some people who have used this medicine developed serious skin problems. Stop using this medicine and tell your doctor right away if you or your child notice a severe skin rash, blistering, peeling, or loosening of the skin, red skin lesions, sores or ulcers on the skin, or fever or chills while you or your child are using this medicine.
This medicine may also increase your risk of developing fractures (broken bones). Ask your doctor about this if you have any concerns.
Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. You should not become pregnant while you are taking this medicine and for 12 weeks after stopping it. Some birth control pills may not work as well while you are using this medicine. Use birth control pills together with another form of birth control, such as condoms, a diaphragm, or contraceptive foam or jelly. If you think you have become pregnant while using the medicine, tell your doctor right away.
This medicine does not decrease the risk of transmitting the HIV infection to others through sexual contact or by contaminated blood. Make sure you understand and practice safe sex, even if your partner also has HIV. Avoid sharing needles with anyone.
This medicine may cause some people to become dizzy, lightheaded, drowsy, or less alert than they are normally. Even if taken at bedtime, it may cause some people to feel drowsy or less alert on arising. Be careful to limit the amount of alcohol that you drink, since alcohol can also make you drowsy. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert.
Your immune system may get stronger when you start taking HIV medicines. Tell your doctor right away if you notice any changes in your health. Sometimes the immune system will start to fight infections that were hidden in your body, such as pneumonia, herpes, or tuberculosis. Autoimmune disorders (such as Graves' disease, polymyositis, and Guillain-Barré syndrome) may also occur.
This medicine may cause you to have excess body fat. Tell your doctor if you notice changes in your body shape, such as an increased amount of fat in the upper back and neck, or around the chest and stomach area. You might also lose fat from the legs, arms, and face.
Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.