Invirase (saquinavir) is an oral tablet that's used as part of an antiretroviral (ARV) regimen to treat human immunodeficiency virus (HIV) in adults and children over 16 years of age. You'll also need to take ritonavir (Norvir) twice daily to help Invirase (saquinavir) work better against the virus. Invirase (saquinavir) belongs to a class of medications called protease inhibitors. Common side effects include nausea, diarrhea, and vomiting.
Treatment of HIV infection in people over 16 years old
Invirase (saquinavir) is a protease inhibitor, which means it blocks a protein called protease. Normally, protease helps to process viral proteins so that the HIV virus can infect healthy cells. By stopping protease from working, Invirase (saquinavir) prevents the virus from making copies of itself and spreading.
Source: DailyMed
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
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
tightness in the chest
trouble breathing
Less common
Blurred vision
cough-producing mucus
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
shivering
skin rash
stomachache
sweating
trouble sleeping
unexplained weight loss
unusual tiredness or weakness
vomiting
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
Back pain
belching
bloated or full feeling
change in taste
decreased interest in sexual intercourse
difficulty having a bowel movement
discouragement
excess air or gas in the stomach or bowels
fear
feeling sad or empty
headache
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 the eyes and cheekbones
passing gas
skin rash, encrusted, scaly, and oozing
skin warts
stomach upset, discomfort, or pain
tiredness
trouble concentrating
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.
Approved for use in adults and children over 16 years old
Safe to take for people with mild to moderate kidney problems
Available as a tablet taken by mouth twice daily
Might raise blood sugar, body fat, and cholesterol levels
Requires regular blood work and lab tests
Interacts with many medications
Invirase (saquinavir) should be taken with ritonavir (Norvir)) and with food (within 2 hours of a meal). This combination helps to keep higher levels of Invirase (saquinavir) in the body, allowing it to work better for you.
Get your routine blood tests done on time while you’re taking Invirase (saquinavir). Lab work is important to make sure that the medication works against the virus, and that it isn't causing unwanted side effects.
Invirase (saquinavir) can interact with many medications. Some medications might need to be stopped or the dose changed before you start HIV ARV regimen. Let your provider or pharmacist know about all the medications you're taking.
Invirase (saquinavir) might raise your blood sugars, which can lead to or worsen diabetes. Talk to your provider to see if you need additional medications to help control your sugar levels during treatment.
Invirase (saquinavir) might cause changes to your heart rhythm. Let your provider know right away if you experience dizziness, fainting, or lightheadedness while taking this medication.
Talk to your provider before stopping Invirase (saquinavir) or any of your HIV medications. Doing so can cause the virus to spread and become harder to treat.
Invirase (saquinavir) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Some medications can interfere with how well your body gets rid of Invirase (saquinavir) from your system. This can affect the amount of Invirase (saquinavir) in your body, how well it works, and the risk of side effects.
Taking certain medications and supplements (like St. John's wort) can lower the amount of Invirase (saquinavir) in your body and make the HIV medication work less well.
Invirase (saquinavir) can also affect how your body gets rid of other medications. This can raise the levels of these medications in the body and raise your risk for side effects. For example, taking Invirase (saquinavir) with certain statins can raise your risk for serious muscle problems.
Because of the potential for serious interactions with Invirase (saquinavir) and various medications, tell your provider and pharmacist about all the medications you take or plan to take.
Risk factors: History of heart problems | Taking medications that affect heart rhythm | Low potassium or magnesium levels | Liver problems
Invirase (saquinavir) can sometimes affect your heart rhythm, which can be serious and life-threatening. Your risk is higher if you have certain conditions, including electrolyte levels that are out of balance and heart rhythm problems. Your risk might also be higher if you're taking other medications that cause heart rhythm problems, such as digoxin (Lanoxin) and beta-blockers, among others. In some instances, you might need to have your heart checked before starting this medication. Get medical attention right away if you feel your chest pounding, have trouble breathing, have chest pain, or feel faint or lightheaded while you're taking Invirase (saquinavir).
Risk factor: Taking protease inhibitor medications
Some people taking protease inhibitor medications like Invirase (saquinavir) developed higher blood sugar levels, which has led to or worsened diabetes. In some cases, people needed to start taking a new medication or their current diabetes treatment plan needed changes to help keep blood sugar under control. If you have a history of diabetes, let your provider know before starting Invirase (saquinavir). Your provider might ask you to check your blood sugar at home to make sure this medication is safe for you.
Risk factors: Hepatitis B or C | History of liver problems | Alcoholism
Some people taking Invirase (saquinavir) have had liver problems, which were sometimes life-threatening. Your provider will order blood tests for you before and during treatment so they can make sure Invirase (saquinavir) is safe for your liver. Let your provider know if you experience signs and symptoms of liver damage, such as sleepiness, nausea, loss of appetite, light-colored stool, upper right stomach pain, yellowing of the skin or eyes, or dark urine.
Some people with a bleeding condition called hemophilia have had more bleeding after starting protease inhibitors like Invirase (saquinavir). In about half of reported cases, people continued taking their protease inhibitor medication after the bleeding stopped. Let your provider know if you notice sudden bleeding or have bleeding that's difficult to stop.
Taking Invirase (saquinavir) along with ritonavir (Norvir) can raise the amount of cholesterol and triglycerides (fats) in your blood. This can put you at higher risk for serious problems. Your provider will check your blood work before and during treatment to keep track of your levels. If your cholesterol levels are too high, you might need to take medications to help keep them under control. Keep in mind that you shouldn't take certain cholesterol medications, such as lovastatin and simvastatin (Zocor), with Invirase (saquinavir) because of the risk of serious muscle damage.
Invirase (saquinavir) oral tablets contain lactose. People with a history of certain genetic problems (e.g., galactose intolerance) are at high risk for diarrhea and other health problems because they can't process it well. For this reason, let your provider know before starting Invirase (saquinavir) if you've a history of genetic conditions.
Taking combination ARV therapy, such as Invirase (saquinavir) with other HIV medications, can cause changes to your immune system called immune reconstitution syndrome. This condition happens when your immune system becomes overly active after you start combination therapy. Your immune system begins to fight off different infections that it was too weak to fight off before you started treatment. In rare cases, your immune response might improve so much with treatment that it starts to attack normal cells in your body (autoimmune). You can develop immune reconstitution syndrome at any time during treatment. Tell your healthcare provider right away if you start having any new symptoms, such as fever, pain, hair loss, bulging eyes, or sweating, after starting Invirase (saquinavir).
Some people taking HIV medications such as Invirase (saquinavir) have experienced changes in body fat. These changes include fat buildup in the back of the neck, in the breast, and in other parts of the body. Some people also lost fat from the legs, arms, and face. It's not clear whether Invirase (saquinavir) causes these changes to body fat, why this happens, and whether it will affect your health in the future. Let your provider know if these changes occur while you're taking Invirase (saquinavir).
Dosage | Quantity | Price as low as | Price per unit |
---|---|---|---|
500mg | 30 tablets | $305.23 | $10.17 |
The typical dose is 1,000 mg by mouth twice a day taken together with 100 mg ritonavir (Norvir) and food.
Your starting dose might differ depending on other HIV medications you've taken in the past.
Using this medicine 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.
Using this medicine 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.
Using this medicine 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.
History of certain heart problems
Low potassium or low magnesium in your blood
Severe liver problems
Taking certain medication that interact with Invirase (saquinavir) (e.g., amiodarone, lovastatin, or simvastatin (Zocor))
Treatment of HIV infection in people over 16 years old
Treatment of HIV infection in adults and children weighing at least 88 pounds
Treatment of HIV infection (used with other antiretroviral medications)
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ClinicalInfoHIV.gov. (n.d.). Boosting.
ClinicalInfoHIV.gov. (n.d.). Immune reconstitution inflammatory syndrome (IRIS).
ClinicalInfoHIV.gov. (n.d.). Protease.
Farzam, K., et al. (2023). QT prolonging drugs. StatPearls.
Genentech, inc. (2020). Invirase- saquinavir mesylate tablet, film coated [package insert]. DailyMed.
HIVinfo.NIH.gov. (2021). Drug resistance.
MedlinePlus. (2020). Glucose-galactose malabsorption.
Thapa, S., et al. (2023). Immune reconstitution inflammatory syndrome. StatPearls.
U.S. Food and Drug Administration. (2017). FDA Drug Safety Communication: Invirase (saquinavir) labels now contain updated risk information on abnormal heart rhythms.
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