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Saquinavir capsules and tablets

Other Names: SQV, Invirase®
Manufacturer: Roche Laboratories

What is it?

Saquinavir capsules and tablets belongs to a group of drugs known as protease inhibitors. It is used to treat HIV, a retrovirus. Retroviruses use the genetic material in the body’s cells to produce more virus which can infect other cells.

How does it work?

Saquinavir interferes with the life cycle of HIV to stop it from producing more virus. Specifically, saquinavir HGC ties up the protease enzyme, which slows the production of new virus to prevent other cells from becoming infected.

How do I take it?

  • Saquinavir is now available as 200 mg capsules and 500mg tablets
  • The dose varies depending upon what other medications are used in combination with saquinavi.
  • Saquinavir should be taken with food to increase absorption of the medication into the bloodstream.

It is extremely important that you take saquinavir HGC and your other antiretroviral medications exactly as directed. You should set up a system that will help you remember to take your medicines so that you do not miss any doses. If you miss a dose, take it as soon as possible; however, if you skip a dose, do not take two doses at once. Do not stop taking the medication for any reason at any time unless you are directed to do so by your study clinician. If you are unable to continue taking your medication due to side effects, you should contact your study clinician immediately.

Special Considerations

  • Saquinavir capsules and tablets should be stored at a controlled room temperature (59 ° to 86 ° F).
  • Please bring your medication bottles (empty and partially used) to each study visit.


Some drugs taken together may have interactions that cause illness or impair the effectiveness of the drugs. Saquinavir has a number of serious drug interactions. You need to be familiar with the names of medications that you are taking and compare them to the medications listed below. Make sure that everyone who is prescribing or dispensing medications to you knows that you are taking saquinavir.

The following medications should not be taken together with saquinavir:

  • astemizole (Hismanal®)
  • cisapride (Propulsid®)
  • dihydroergotamine
  • ergotamine
  • midazolam (Versed®)
  • terfenadine (Seldane®)
  • triazolam (Halcion®)

Inform your study clinician if you are taking any of the following medications:

  • Anticonvulsants (phenytoin, carbamazepine, phenobarbital)
  • dexamethasone
  • ifabutin (Mycobutin®)
  • lovastatin (Mevacor®)
  • rifampin
  • St. Johns Wort (hypericum perforatum)
  • sildenafil (Viagra®)
  • simvastatin (Zocor®)

Other antiretroviral drugs may increase (ritonavir, nelfinavir, or delavirdine) or decrease (nevirapine or efavirenz) the amount of saquinavir HGC that is in your body. The dose of saquinavir or other antiretroviral medications may need to be adjusted.

Side Effects

Not everyone experiences side effects. When they do occur, they may be mild, moderate or severe. Some side effects cannot be felt by the patient but can be found through laboratory tests, so it is important to see your study clinician regularly for checkups so that side effects can be detected early and treated.

The most common side effects of saquinavir are diarrhea, bloating, and gas. Other less common side effects include fatigue (feeling tired), headache, muscle aches, nausea, and vomiting. If these side effects occur and are severe, last for more than a few days, or seem to be getting worse, they should be reported to your study clinician

Increases in blood sugar or the development of diabetes has been reported in some patients taking protease inhibitors. Symptoms include increased thirst or hunger, weight loss, increased need to urinate, fatigue, or dry, itchy skin. Please contact your study clinician if any of these side effects occur.

Also, a condition called lipodystrophy (abnormal use of fats in the body) has been reported in patients taking protease inhibitors. Symptoms vary among individuals, but they may include accumulation of fat tissue in the stomach area or the upper back, and a loss of fat in other areas of the body (possibly in the arms, legs, and face). Some people have experienced increases in cholesterol and triglycerides that have required the use of lipid lowering medications.

The benefits of taking protease inhibitors far outweigh the risk of developing lipodystrophy or diabetes. Therefore, at this time, we strongly encourage you to take your medications exactly as prescribed. Notify your study clinician if any of these side effects are bothersome and may prevent you from taking your medication.

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