Drugs Information Online
Drugs and diseases reference index

Drugs and diseases reference index

Drugs reference index «saquinavir»

saquinavir (Oral route)


Commonly used brand name(s):

In the U.S.

  • Invirase

Available Dosage Forms:

  • Capsule, Liquid Filled
  • Tablet
  • Capsule

Therapeutic Class: Antiretroviral Agent

Pharmacologic Class: Protease Inhibitor

Uses For saquinavir

Saquinavir is used, usually in combination with other HIV medicines including ritonavir (e.g., Norvir), in the treatment of the infection caused by the human immunodeficiency virus (HIV). HIV is the virus that causes acquired immune deficiency syndrome (AIDS).

Saquinavir 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. This may help delay the development of problems usually related to AIDS or HIV disease. Saquinavir will not keep you from spreading HIV to other people. People who receive saquinavir may continue to have other problems usually related to AIDS or HIV disease.

saquinavir is available only with your doctor's prescription.

Before Using saquinavir

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 saquinavir, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to saquinavir or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies have not been performed on the relationship of age to the effects of saquinavir in children and teenagers younger than 16 years of age. Safety and efficacy have not been established.


Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of saquinavir in the elderly. However, elderly patients are more likely to have age-related liver, kidney, or heart problems, which may require caution in patients receiving saquinavir.


Pregnancy CategoryExplanation
All TrimestersBAnimal studies have revealed no evidence of harm to the fetus, however, there are no adequate studies in pregnant women OR animal studies have shown an adverse effect, but adequate studies in pregnant women have failed to demonstrate a risk to the fetus.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Using saquinavir with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

  • Amiodarone
  • Astemizole
  • Bepridil
  • Cisapride
  • Dihydroergotamine
  • Dronedarone
  • Ergoloid Mesylates
  • Ergonovine
  • Ergotamine
  • Flecainide
  • Methylergonovine
  • Midazolam
  • Pimozide
  • Propafenone
  • Quinidine
  • Ranolazine
  • Rifampin
  • Sildenafil
  • Silodosin
  • Terfenadine
  • Tolvaptan
  • Triazolam

Using saquinavir with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Amprenavir
  • Colchicine
  • Darunavir
  • Dasatinib
  • Digoxin
  • Eplerenone
  • Everolimus
  • Fluticasone
  • Fosamprenavir
  • Fusidic Acid
  • Garlic
  • Iloperidone
  • Ixabepilone
  • Lapatinib
  • Loperamide
  • Lovastatin
  • Nilotinib
  • Pazopanib
  • Rifabutin
  • Romidepsin
  • Salmeterol
  • Simvastatin
  • St John's Wort
  • Sunitinib
  • Tadalafil
  • Tamsulosin
  • Temsirolimus
  • Tipranavir
  • Topotecan
  • Venlafaxine

Using saquinavir with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Alfentanil
  • Amlodipine
  • Atazanavir
  • Atorvastatin
  • Carbamazepine
  • Cerivastatin
  • Cimetidine
  • Clarithromycin
  • Cyclosporine
  • Dapsone
  • Delavirdine
  • Dexamethasone
  • Diltiazem
  • Efavirenz
  • Felodipine
  • Fentanyl
  • Flunarizine
  • Fosphenytoin
  • Gallopamil
  • Indinavir
  • Isradipine
  • Itraconazole
  • Ketoconazole
  • Lacidipine
  • Maraviroc
  • Methadone
  • Nelfinavir
  • Nevirapine
  • Nicardipine
  • Nifedipine
  • Nilvadipine
  • Nimodipine
  • Nisoldipine
  • Nitrendipine
  • Omeprazole
  • Phenobarbital
  • Phenytoin
  • Rifapentine
  • Sirolimus
  • Tacrolimus
  • Verapamil
  • Voriconazole
  • Warfarin

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

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

  • Alcoholism or
  • Cirrhosis of the liver or
  • Hepatitis B or
  • Hepatitis C or
  • Liver problems—Effects of saquinavir may be increased because of slower removal of the medicine from the body; also saquinavir has been reported to cause unwanted effects on the liver.
  • Diabetes mellitus or
  • Hemophilia (bleeding problem) or
  • Hypercholesterolemia (high cholesterol in the blood) or
  • Hyperglycemia (high blood sugar)—Use with caution. May make these conditions worse.
  • Lactose intolerance—Use with caution. Saquinavir capsules contain lactose.
  • Liver disease, severe—Should not be used in patients with this condition.

Proper Use of saquinavir

It is important that saquinavir be taken with food in order to work properly. Take saquinavir within 2 hours after a meal.

Take saquinavir exactly as directed by your doctor. Do not take it more often, and do not take it for a longer time than your doctor ordered. Also, do not stop taking saquinavir without checking with your doctor first.

Saquinavir capsules or tablets (Invirase®) should always be taken together, at the same time, with ritonavir (Norvir®). Take all other medicines your doctor has prescribed at the right time of the day. This will make your medicines work better.

Keep taking saquinavir for the full time of treatment, even if you begin to feel better.

saquinavir works best when there is a constant amount in the blood. To help keep the amount constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times, day and night. For example, if you are to take three doses a day, the doses should be spaced about 8 hours apart. If you need help in planning the best times to take your medicine, check with your health care professional.

Only take medicine that your doctor has prescribed specially for you. Do not share your medicine with others.


The dose of saquinavir 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 saquinavir. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For treatment of HIV infection:
    • For oral dosage form (capsules or tablets):
      • Adults and teenagers older than 16 years of age—1000 milligrams (mg) two times a day, together with ritonavir (e.g., Norvir®). Your doctor will tell you the dose of ritonavir that you should take.
      • Children and teenagers up to 16 years of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of saquinavir, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.


Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions While Using saquinavir

It is very important that your doctor check your progress at regular visits to make sure that saquinavir is working properly. Blood tests may be needed to check for unwanted effects.

Do not take any other medicines without checking with your doctor first. To do so may increase the chance of side effects from saquinavir or other medicines.

You should not take saquinavir if you are also taking medicine for heart rhythm problems (e.g., amiodarone, bepridil, flecainide, propafenone, quinidine, Pacerone®, Quinora®, Rhythmol®, Tambocor®, Vascor®), ergot medicines (e.g., dihydroergotamine, ergonovine, ergotamine, methylergonovine, Cafergot®, D.H.E. 45®, Ergomar®, Ergotrate®, Methergine®, Wigraine®), medicine to lower cholesterol (e.g., atorvastatin, lovastatin, simvastatin, Altocor®, Lipitor®, Mevacor®, Zocor®), astemizole (Hismanal®), cisapride (Propulsid®), fluticasone (Flonase®), midazolam (Versed®), pimozide (Orap®), rifampin (Rifadin®), terfenadine (Seldane®), tipranavir (Aptivus®), or triazolam (Halcion®). Taking any of them together with saquinavir may increase the chance of serious side effects.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (e.g., St. John's wort, garlic capsules) or vitamin supplements.

saquinavir may decrease the effects of some oral contraceptives (birth control pills). To keep from getting pregnant, use an additional form of birth control such as condoms, a diaphragm, or contraceptive foams or jellies.

saquinavir may increase blood sugar levels. Check with your doctor if you notice a change in the results of your blood or urine sugar tests.

You should not breastfeed if you have HIV or AIDS, because you may give the infection to your baby through your breast milk.

Saquinavir 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, and use them every time you have vaginal, anal, or oral sex. The use of a spermicide (such as nonoxynol-9) may also help prevent the spread of HIV if it is not irritating to the vagina, rectum, or mouth. Spermicides have been shown to kill HIV in lab tests. Do not use oil-based jelly, cold cream, baby oil, or shortening as a lubricant—these products can cause the condom to break. Lubricants without oil, such as K-Y Jelly, are recommended. Women may wish to carry their own condoms. Birth control pills and diaphragms will help protect against pregnancy, but they will not prevent someone from giving or getting the AIDS virus. If you inject drugs, get help to stop. Do not share needles or equipment with anyone. In some cities, more than half of the drug users are infected, and sharing even 1 needle or syringe can spread the virus. If you have any questions about this, check with your health care professional.

When you start taking HIV medicines, your immune system may get stronger. If you have certain infections, such as pneumonia or tuberculosis, you may notice new symptoms when your body tries to fight them. If this occurs, be sure to tell your doctor right away.

saquinavir may cause you to have excess body fat. Tell your doctor if you notice changes in your body shape, such as an increased amount of fat in the upper back and neck, or around the chest and stomach area; or a loss of fat from the legs, arms, and face.

saquinavir Side Effects

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:

More common
  • Chest pain
  • cough
  • fever or chills
  • increased amount of fat in the upper back and neck, or around the chest and stomach area
  • loss of fat from the legs, arms, and face
  • shortness of breath
  • sneezing
  • sore throat
  • tightness in chest
  • troubled breathing
  • wheezing
Less common
  • Blurred vision
  • cough-producing mucus
  • diarrhea
  • difficulty breathing
  • dry mouth
  • flushed, dry skin
  • fruit-like breath odor
  • general feeling of discomfort or illness
  • headache
  • increased hunger
  • increased thirst
  • increased urination
  • joint pain
  • loss of appetite
  • loss of consciousness
  • muscle aches and pains
  • nausea
  • runny nose
  • shivering
  • skin rash
  • sore throat
  • stomachache
  • sweating
  • trouble sleeping
  • troubled breathing
  • unexplained weight loss
  • unusual tiredness or weakness
  • vomiting
  • Burning or prickling sensation
  • confusion
  • dehydration
  • dry or itchy skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common
  • Abdominal pain
  • acid or sour stomach
  • back pain
  • belching
  • bloated full feeling
  • change in taste
  • decreased interest in sexual intercourse
  • difficulty having a bowel movement (stool)
  • discouragement
  • excess air or gas in stomach or intestines
  • fear
  • feeling sad or empty
  • headache
  • heartburn
  • inability to have or keep an erection
  • indigestion
  • irritability
  • lack of appetite
  • loss in sexual ability, desire, drive, or performance
  • loss of interest or pleasure
  • mouth ulcers
  • nervousness
  • pain or tenderness around eyes and cheekbones
  • passing gas
  • skin rash, encrusted, scaly, and oozing
  • skin warts
  • sleeplessness
  • stomach upset, discomfort, or pain
  • stuffy nose
  • tiredness
  • trouble concentrating
  • unable to sleep
  • weakness

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

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

The information contained in the Thomson Healthcare (Micromedex) products as delivered by Drugs.com is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. Talk to your doctor, nurse or pharmacist before taking any prescription or over the counter drugs (including any herbal medicines or supplements) or following any treatment or regimen. Only your doctor, nurse, or pharmacist can provide you with advice on what is safe and effective for you.

The use of the Thomson Healthcare products is at your sole risk. These products are provided "AS IS" and "as available" for use, without warranties of any kind, either express or implied. Thomson Healthcare and Drugs.com make no representation or warranty as to the accuracy, reliability, timeliness, usefulness or completeness of any of the information contained in the products. Additionally, THOMSON HEALTHCARE MAKES NO REPRESENTATION OR WARRANTIES AS TO THE OPINIONS OR OTHER SERVICE OR DATA YOU MAY ACCESS, DOWNLOAD OR USE AS A RESULT OF USE OF THE THOMSON HEALTHCARE PRODUCTS. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE OR USE ARE HEREBY EXCLUDED. Thomson Healthcare does not assume any responsibility or risk for your use of the Thomson Healthcare products.

  • Saquinavir Detailed Consumer Information (PDR)
  • Saquinavir MedFacts Consumer Leaflet (Wolters Kluwer)
  • Fortovase Prescribing Information (FDA)
  • Invirase Prescribing Information (FDA)
  • Invirase MedFacts Consumer Leaflet (Wolters Kluwer)
  • Invirase Consumer Overview