Nelfinavir is an antiviral medication that prevents human immunodeficiency virus (HIV) cells from multiplying in your body.

Nelfinavir is used to treat HIV, which causes acquired immunodeficiency syndrome (AIDS). Nelfinavir is not a cure for HIV or AIDS.

Nelfinavir may also be used for purposes not listed in this medication guide.

It is not known whether this impurity has caused harm to anyone taking nelfinavir, and it is important to keep treating your condition. Children and pregnant women should not take nelfinavir as a "first-line" treatment. If you already take nelfinavir your doctor may recommend that you keep taking it. Do not stop taking nelfinavir or change your dose without your doctor's advice.

Do not take nelfinavir with alfuzosin (Uroxatrol), amiodarone (Cordarone, Pacerone), lovastatin (Mevacor, Altoprev, Advicor), quinidine (Quin-G), pimozide (Orap), midazolam (Versed), sildenafil (Revatio for pulmonary arterial hypertension), simvastatin (Zocor, Simcor, Vytorin, Juvisync), triazolam (Halcion), or an ergot medicine such as Ergomar, Cafergot, Wigraine, D.H.E. 45, Migranal, or Methergine. These drugs can cause life-threatening side effects if you use them while you are taking nelfinavir.

There are many other medicines that can interact with nelfinavir. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Taking this medication will not prevent you from passing HIV to other people. Do not have unprotected sex or share razors or toothbrushes. Talk with your doctor about safe ways to prevent HIV transmission during sex. Sharing drug or medicine needles is never safe, even for a healthy person.

You should not take this medication if you are allergic to nelfinavir, or if you have moderate or severe liver disease.

Do not take nelfinavir with alfuzosin (Uroxatrol), amiodarone (Cordarone, Pacerone), lovastatin (Mevacor, Altoprev, Advicor), quinidine (Quin-G), pimozide (Orap), midazolam (Versed), sildenafil (Revatio for pulmonary arterial hypertension), simvastatin (Zocor, Simcor, Vytorin, Juvisync), triazolam (Halcion), or an ergot medicine such as Ergomar, Cafergot, Wigraine, D.H.E. 45, Migranal, or Methergine. These medications can cause life-threatening side effects if you use them while you are taking nelfinavir.

To make sure you can safely take nelfinavir, tell your doctor if you have any of these other conditions:

• liver disease;

• kidney disease;

• diabetes;

• a bleeding disorder such as hemophilia; or

• high cholesterol or triglycerides.

If you are pregnant, your name may be listed on a pregnancy registry. This is to track the outcome of the pregnancy and to evaluate any effects of nelfinavir on the baby.

FDA pregnancy category B. This medication is not expected to be harmful to an unborn baby, but HIV can be passed to your baby if you are not properly treated during pregnancy. Tell your doctor if you are pregnant or plan to become pregnant during treatment. Take all of your HIV medicines as directed to control your infection.

Nelfinavir can make birth control pills less effective. Ask your doctor about using a non-hormone method of birth control (such as a condom or diaphragm with spermicide) to prevent pregnancy while taking nelfinavir.

You should not breast-feed while you are using nelfinavir. Women with HIV or AIDS should not breast-feed at all. Even if your baby is born without HIV, you may still pass the virus to the baby in your breast milk.

Do not give this medication to a child younger than 2 years old.