In the U.S.—

• Antiviral, systemic

Emtricitabine (em-tri-SIT-uh-bean) is a type of medicine called an HIV (human immunodeficiency virus) nucleoside reverse transcriptase inhibitor (NRTI). Emtricitabine is always used with other anti-HIV medicines to treat people with HIV infection.

HIV infection destroys CD4 (T) cells, which are important to the immune system in your body. The immune system helps fight infection. After a large number of T cells are destroyed, acquired immune deficiency syndrome (AIDS) develops.

Emtricitabine helps to block HIV reverse transcriptase, a chemical in your body (enzyme) that is needed for HIV to multiply. Emtricitabine may lower the amount of HIV in your blood (viral load). Emtricitabine may also help to increase the number of T cells called CD4 cells. Lowering the amount of HIV in your blood lowers the chance of you having problems that happens when your immune system is weak.

Emtricitabine will not cure or prevent HIV infection or AIDS; however, it helps keep HIV from reproducing and appears to slow down the destruction of the immune system.

Emtricitabine will not keep you from spreading HIV to other people. People who receive this medicine may continue to have the problems usually related to AIDS or HIV disease

This medicine is available only with your doctor's prescription, in the following dosage form(s):

Oral
• Capsules (U.S.)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For emtricitabine, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to emtricitabine or lamivudine. Also tell your doctor and pharmacist if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Studies in pregnant women have not been done. However, emtricitabine has not been shown to cause birth defects or other problems in animal studies. Also, it is not known whether emtricitabine reduces the chances that a baby born to an HIV-infected mother will also be infected. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—It is not known whether emtricitabine passes into human breast milk. However, if your baby does not already have the AIDS virus, there is a chance that you could pass it to your baby by breast-feeding. Talk to your doctor first if you are thinking about breast-feeding your baby.

Children—This medicine is typically not used in patients under 18 years of age.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. Elderly patients are more likely to have other medical problems and they may take a lower dose than some younger adults.

• Hepatitis B virus (HBV) infectionEmtricitabine is not used to treat patients with hepatitis B virus infection. You may receive emtricitabine to treat your HIV infection even if you also have hepatitis B virus infection. Your doctor will want to follow you closely for several months and do regular medical exams once you stop taking emtricitabine.

• Kidney problemsYour doctor may want to lower your dose if you have kidney problems.

• Obesity (overweight) or
• Using nucleoside medicine for a long timeThese conditions might increase your chances of getting lactic acidosis (buildup of acid in your blood) or liver problems. This is more common in females.

Dosing—

The dose of emtricitabine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of emtricitabine. If your dose is different, do not change it unless your doctor tells you to do so. Do not share your medicine with others.

It is important to take this medicine in combination with another anti-HIV medicine and to take it exactly as your doctor tells you to. You should take your medicine at the same time every day to avoid missing doses. It is very important that you do not miss any doses of this medicine or of your other anti-HIV medicines.

Do not take other medicines unless they have been discussed with your doctor. Tell your healthcare professional about all of the medicines and dietary supplements that you take. Keep a complete list of all the medications that you take. Make a new list when medications are added or stopped. Make sure you show this list to your doctor or pharmacist each time you have a visit or refill a prescription.

When your emtricitabine supply runs low, get more from your pharmacy or from your healthcare provider. This is very important because the amount of virus in your blood may increase if the medicine is stopped, even for a short time. The virus may develop resistance to emtricitabine and be harder to treat.

• For oral dosage form (capsules):
  • For treatment of HIV infection
    • Adults—Oral, 200 milligrams (mg) taken once a day. This medicine can be taken with or without food. Your doctor may want to change the dose if you have certain medical problems.
    • Children—This medicine is not usually used in children under the age of 18 years.

Missed dose—

If you forget to take emtricitabine take it as soon as you remember that day. Do not take more than 1 dose of emtricitabine in a day. Do not take 2 doses at the same time. Call your healthcare provider or pharmacy if you are not sure what to do.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Do not keep your medicine in places that are too hot or too cold.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Ask your health care professional how you should dispose of any medicine you do not use. Be sure that any discarded medicine is out of the reach of children.

It is very important that you read the patient information when you start taking this medicine and each time you get a refill. There may be new information for you.

It is very important that your doctor check you at regular visits to be sure this medicine is working properly. You should remain under the care of a doctor while taking emtricitabine.

Emtricitabine does not decrease the risk of transmitting the HIV infection to others through sexual contact or by contamination through blood. HIV may be acquired from or spread to others through infected body fluids, including blood, vaginal fluid, or semen. If you are infected, it is best to avoid any sexual activity involving an exchange of body fluids with other people. If you do have sex, always wear (or have your partner wear) a condom (“rubber”). Only use condoms made of latex or polyurethane and use them every time you have contact with semen, vaginal secretions, or blood. Also, do not share needles or equipment with anyone or use dirty needles. If you have any questions about this, check with your health care professional.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

• Incidence unknown
  • Abdominal discomfort;  decreased appetite ;  diarrhea;  fast, shallow breathing;  general feeling of discomfort;  muscle pain or cramping;  nausea;  shortness of breath;  sleepiness;  unusual tiredness or weakness 
  
  

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

• cough;  diarrhea;  headache;  lack or loss of strength;  nausea;  runny nose;  sneezing;  stuffy nose 

• Less common
  • Abdominal pain;  abnormal dreams;  acid or sour stomach;  belching;  burning, crawling, itching, numbness, prickling, "pins and needles”, or tingling feelings;  depression problems;  difficulty in moving;  dizziness;  heartburn;  indigestion;  joint pain;  muscle aching or cramping ;  muscle pain or stiffness;  numbness or tingling of hands, feet, or face;  pain in joints;  rash;  stomach discomfort, upset, or pain;  sleeplessness;  swollen joints;  trouble sleeping;  unable to sleep;  unsteadiness or awkwardness ;  vomiting;  weakness in arms, hands, legs, or feet 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.