Fosamprenavir can cause serious, life-threatening side effects. These include severe skin reactions or rash.
If you get a rash with any of the following symptoms, stop taking fosamprenavir and contact your health care provider or get medical help right away:
- Hives or sores in your mouth, or your skin blisters and peels.
- Trouble swallowing or breathing.
- Swelling of your face, eyes, lips, tongue, or throat.
Taking fosamprenavir with certain other medicines may result in serious and/or life-threatening side effects. Tell your health care provider about other medicines you take.
While taking fosamprenavir, it is important to keep all of your appointments with your health care provider.
What is fosamprenavir?
Fosamprenavir is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV infection in adults and children 4 weeks of age and older. Fosamprenavir is always used in combination with other anti-HIV medicines.
Fosamprenavir is a type of anti-HIV medicine called a protease inhibitor (PI). Fosamprenavir works by blocking protease, an HIV enzyme. This prevents HIV from replicating and lowers the amount of HIV in the blood.
Fosamprenavir does not cure HIV/AIDS. It is not known if fosamprenavir reduces the risk of passing HIV to other people.
What should I tell my health care provider before taking fosamprenavir?
Before taking fosamprenavir, tell your health care provider:
- If you are allergic to fosamprenavir, sulfa medicines, or any other medicines.
- If you have liver problems, including hepatitis B virus (HBV) or hepatitis C virus (HCV) infection.
- If you have kidney problems.
- If you have diabetes or high blood sugar (hyperglycemia).
- If you have hemophilia.
- If you have any other medical conditions.
- If you are pregnant or plan to become pregnant. Whether fosamprenavir can harm an unborn baby is unknown.
- If you are breastfeeding or plan to breastfeed. Do not breastfeed if you are infected with HIV or are taking fosamprenavir.
- About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Fosamprenavir may affect the way other medicines or products work, and other medicines or products may affect how fosamprenavir works. Taking fosamprenavir together with certain medicines or products may cause serious and/or life-threatening side effects.
How should I take fosamprenavir?
Fosamprenavir comes in two forms:
- 700-mg tablets (brand name: Lexiva).
- 50-mg/mL oral suspension (brand name: Lexiva).
Take fosamprenavir according to your health care provider’s instructions.
Take fosamprenavir tablets with or without food. Adults should take the fosamprenavir oral suspension without food. Children should take the oral suspension with food. If your child vomits within 30 minutes after taking a dose of fosamprenavir, the dose should be repeated. Shake the oral suspension vigorously before each use.
Always take fosamprenavir in combination with other anti-HIV medicines.
If you take too much fosamprenavir, contact your local poison control center (1-800-222-1222) or go to the nearest hospital emergency room right away.
For more information on how to take fosamprenavir, see the FDA drug label from DailyMed. (DailyMed is a federal website that includes the most recent drug labels submitted to FDA.)
What should I do if I forget a dose?
Take the missed dose as soon as you remember it. But if it is almost time for your next dose, skip the missed dose and just take your next dose at the regular time. Do not take two doses at the same time to make up for a missed dose.
What side effects can fosamprenavir cause?
Fosamprenavir can cause serious, life-threatening side effects. These include severe skin reactions or rash. Taking fosamprenavir with certain other medicines may cause serious and/or life-threatening side effects. (See the WARNING above.)
Other possible side effects of fosamprenavir include:
- Liver problems.
- Diabetes and high blood sugar (hyperglycemia).
- Changes in body fat (lipodystrophy).
- Changes in the immune system (immune reconstitution inflammatory syndrome).
- Changes in blood tests.
- Increased bleeding in some people with hemophilia.
- Kidney stones. (Contact your health care provider right away if you have pain in your side, blood in your urine, or pain when you urinate.)
Tell your health care provider if you have any side effect that bothers you or that does not go away.
These are not all the possible side effects of fosamprenavir. Ask your health care provider or pharmacist for more information on possible side effects of fosamprenavir.
How should fosamprenavir be stored?
- Store fosamprenavir tablets at room temperature, 68°F to 77°F (20°C to 25°C). Keep the container tightly closed.
- Store fosamprenavir oral suspension between 41°F and 86°F (5°C to 30°C). Refrigeration of fosamprenavir oral suspension may improve taste for some people. Do not freeze the oral suspension.
- Safely throw away fosamprenavir that is no longer needed or expired (out of date).
- Keep fosamprenavir and all medicines out of reach of children.
Where can I find more information about fosamprenavir?
More information about fosamprenavir is available:
Last Reviewed: September 13, 2012
Last Updated: August 23, 2013