Amprenavir (Systemic)

Brand Names : Agenerase

Before Using This Medicine

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 amprenavir, the following should be considered:

Allergies - Tell your doctor if you have ever had any unusual or allergic reaction to amprenavir or sulfa medicines. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy - Amprenavir has not been studied in pregnant women. However, studies in animals have shown that amprenavir causes birth defects and other problems. Amprenavir capsules should only be used during pregnancy if the benefit outweighs the potential risk. Amprenavir oral solution should only be used during pregnancy if the benefit outweighs the potential risk. 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 amprenavir passes into breast milk. However, breast-feeding is not recommended in patients with HIV-infection because of the risk of passing the HIV virus on to the nursing infant. Mothers should not breast-feed while taking amprenavir.

Children - This medicine has been tested in children 4 years of age and older. In effective doses, the medicine has not been shown to cause different side effects or problems than it does in adults.

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. However, specific side effects may be especially likely to occur in elderly patients, who are usually more sensitive than younger adults to the effects of amprenavir. There is no specific information comparing use of amprenavir in the elderly with use in other age groups.

Other medicines - Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking amprenavir, it is especially important that your health care professional know if you are taking any other medicines (prescription or over-the-counter [OTC], especially the following:

• Alcohol - the ingredients in amprenavir oral solution should not be mixed with alcohol. Do not use together.

• Amiodarone or
• Lidocaine (systemic) or
• Quinidine or
• Tricyclic antidepressants (amitriptyline [e.g., Elavil], amoxapine [e.g., Asendin], clomipramine [e.g., Anafranil], desipramine [e.g., Norpramin], doxepin [e.g., Sinequan], imipramine [e.g., Tofranil], nortriptyline [e.g., Aventyl, Pamelor], protriptyline [e.g., Vivactil], trimipramine [e.g., Surmontil] - There is a possibility that amprenavir may interfere with the removal of these medicines from the body, which could lead to serious side effects

• Antacids or
• Didanosine (e.g., Videx) - Use of antacids or didanosine with amprenavir may keep amprenavir from working properly if taken close together. Antacids and didanosine should be taken at least one hour before or after amprenavir.

• Bepridil (e.g. Vascor) - Use of bepridil and amprenavir together can cause life-threatening reactions. Use together with caution.

• Carbamazepine (e.g., Tegretol) or
• Phenobarbital or
• Phenytoin (e.g., Dilantin) - Use of these medicines with amprenavir may cause amprenavir to be less effective. Use with caution.

• Cyclosporine (e.g., Sandimmune) or
• Rapamycin (e.g., Rapamune) or
• Tacrolimus (e.g., Prograf) - Use with amprenavir may cause more side effects

• Cisapride (e.g., Propulsid) - Do not use with amprenavir as life-threatening reactions can occur.

• Delavirdine (e.g., Rescriptor) - Use with amprenavir may lead to a possible resistance to delavirdine. They should not be administered together.

• Disulfiram (e.g., Antabuse) or
• Metronidazole (e.g., Flagyl) - Use of these medicines with amprenavir oral solution can be dangerous. Do not use together.

• Ergot derivatives (e.g., D.H.E., Methergine, Ergotrate) - Use of these medicines with amprenavir can cause serious side effects. Do not use together.

• Itraconazole (e.g., Sporanox) or
• Ketoconazole (e.g., Nizoral) - The dose of these medicines may need to be lowered.

• HMG-CoA reductase inhibitors (atorvastatin [e.g., Lipitor], lovastatin [e.g., Mevacor], simvastatin [e.g., Zocor] - Use of amprenavir may cause a high blood level of these medicines. If you are on atorvastatin while on amprenavir, use the lowest possible dose or consider using other HMG-CoA reductase inhibitors.

• Midazolam (e.g., Versed) or
• Triazolam (e.g., Halcion) - Use of these medicines with amprenavir can cause serious reactions and should not be used together.

• Oral contraceptives - Use of these medicines may cause amprenavir to be less effective. Alternate methods of birth control are recommended.

• Pimozide (e.g., Orap) - Use of this medicine with amprenavir can cause serious reactions. Do not use together.

• Rifabutin (e.g., Mycobutin) - Use of amprenavir can cause increased blood levels of rifabutin. Rifabutin can cause decreased blood levels of amprenavir.

• Rifampin - Use of this medicine may lead to possible resistance to amprenavir. Do not use together.

• Ritonavir capsules (e.g., Norvir) - Using this medicine with amprenavir can cause an increase in the amount of amprenavir your body gets.

• Ritonavir oral solution - Amprenavir and ritonavir oral solution may remain in your body for longer periods of time. Use of these medicines together is not recommended.

• Saquinavir (e.g., Forovase, Invirase) - Amprenavir levels may be decreased.

• Sildenafil (e.g., Viagra) - Use of this medicine with amprenavir may increase the amount of sildenafil in the body and may increase the chance for side effects, such as low blood pressure, changes in vision, and erection of the penis lasting more than 4 hours. Use a reduced dose of sildenafil.

• St. John's wort - This medicine can decrease the blood levels of amprenavir in your body. It may also result in resistance to amprenavir.

• Warfarin (e.g., Coumadin) - Amprenavir may decrease your blood clotting time and make you bleed more easily.

Other medical problems - The presence of other medical problems may affect the use of amprenavir. Make sure you tell your doctor if you have any other medical problems, especially:

• Diabetes mellitus or
• Hemophilia - Amprenavir may make these conditions worse

• Kidney failure or
• Liver failure - Amprenavir oral solution should not be used because serious side effects may occur

• Liver disease - Effects of amprenavir may be increased because of slower removal of amprenavir from the body

• Vitamin K deficiency - The high amounts of vitamin E in amprenavir dosage forms may increase the chance of bleeding problems in patients who are deficient in vitamin K