Last updated on RxList: 12/13/2021
Invirase Side Effects Center

What Is Invirase?

Invirase (saquinavir mesylate) is a type of antiviral medication called a protease inhibitor used to treat HIV, which causes acquired immunodeficiency syndrome (AIDS). It is not a cure for HIV or AIDS.

What Are Side Effects of Invirase?

Common side effects of Invirase include:

  • diarrhea,
  • nausea,
  • vomiting,
  • stomach pain,
  • tiredness, or
  • changes in the shape or location of body fat (especially in your arms, legs, face, neck, breasts, and waist).

Contact your doctor if you experience serious side effects of Invirase including:

  • stabbing chest pain,
  • fever,
  • infection,
  • rapid heart rate,
  • weakness, or
  • problems breathing or swallowing

Dosage for Invirase?

The recommended dose of Invirase for adults over the age of 16 years is 1000-mg twice daily (5 x 200-mg capsules or 2 x 500-mg tablets) in combination with ritonavir 100-mg twice daily. Ritonavir should be taken at the same time as Invirase, and both should be taken within 2 hours after a meal.

What Drugs, Substances, or Supplements Interact with Invirase?

Invirase may interact with digoxin, fluticasone, garlic, St. John's wort, antibiotics, antidepressants, blood thinners, calcium channel blockers, cholesterol-lowering medicines, drugs that weaken the immune system, other HIV /AIDS medicines, insulin or oral diabetes medications, medicines to treat erectile dysfunction, or seizure medications. Other medicines may interact with Invirase. Tell your doctor all medications and supplements you use.

Invirase During Pregnancy and Breastfeeding

Tell your doctor if you are pregnant before using Invirase. It is unknown if this drug passes into breast milk. Because breast milk can transmit HIV, do not breastfeed.

Additional Information

Our Invirase (saquinavir mesylate) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Invirase Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • heart rhythm problems--fast or pounding heartbeats, fluttering in your chest, shortness of breath, sudden dizziness (like you might pass out);
  • high blood sugar--increased thirst, increased urination, dry mouth, fruity breath odor; or
  • liver problems--upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Saquinavir affects your immune system, which may cause certain side effects (even weeks or months after you've taken this medicine). Tell your doctor if you have:

  • signs of a new infection--fever, night sweats, swollen glands, cold sores, cough, wheezing, diarrhea, weight loss;
  • trouble speaking or swallowing, problems with balance or eye movement, weakness or prickly feeling; or
  • swelling in your neck or throat (enlarged thyroid), menstrual changes, impotence.

Common side effects may include:

  • nausea, vomiting, diarrhea, stomach pain;
  • tired feeling; or
  • changes in the shape or location of body fat (especially in your arms, legs, face, neck, breasts, and waist).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Invirase (Saquinavir Mesylate)


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Invirase Professional Information


The following adverse reactions are discussed in greater detail in other sections of the labeling:

  • PR Interval Prolongation [see WARNINGS AND PRECAUTIONS]
  • QT Interval Prolongation [see WARNINGS AND PRECAUTIONS]

Clinical Trial Experience In Adult Subjects

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

The original INVIRASE safety database consisted of a total of 574 adult subjects who received 600 mg of saquinavir mesylate capsules (hard gel) alone or in combination with zidovudine (ZDV) or zalcitabine (ddC). Combination dosing with ritonavir is based on 352 HIV-1 infected subjects and 166 healthy subjects who received various combinations of either saquinavir mesylate capsules (hard gel or soft gel) with ritonavir.

The recommended dose of INVIRASE is 1,000 mg twice daily co-administered with ritonavir 100 mg twice daily. Table 1 lists Grade 2, 3 and 4 adverse events that occurred in ≥2% of subjects receiving saquinavir mesylate capsules (soft gel) with ritonavir (1000/100 mg bid).

Table 1 Grade 2, 3 and 4 Adverse Events (All Causalitya) Reported in ≥2% of Adult Subjects in the MaxCmin 1 Study of Saquinavir Mesylate Capsules (soft gel) in Combination with Ritonavir 1000/100 mg Twice a Day

Adverse EventsSaquinavir Mesylate Capsules (soft gel) 1000 mg plus Ritonavir 100 mg bid (48 weeks)
n (%=n/N)
Endocrine Disorders
  Diabetes mellitus/hyperglycemia4 (3)
  Lipodystrophy8 (5)
Gastrointestinal Disorders
  Nausea16 (11)
  Vomiting11 (7)
  Diarrhea12 (8)
  Abdominal Pain9 (6)
  Constipation3 (2)
General Disorders and Administration Site Conditions
  Fatigue9 (6)
  Fever5 (3)
Musculoskeletal Disorders
  Back Pain3 (2)
Respiratory Disorders
  Pneumonia8 (5)
  Bronchitis4 (3)
  Influenza4 (3)
  Sinusitis4 (3)
Dermatological Disorders
  Rash5 (3)
  Pruritus5 (3)
  Dry lips/skin3 (2)
  Eczema3 (2)
a Includes events with unknown relationship to study drug

Limited experience is available from three trials investigating the pharmacokinetics of the INVIRASE 500-mg film-coated tablet compared to the 200-mg saquinavir mesylate capsules (hard gel) in healthy volunteers (n=140). In two of these trials, saquinavir was combined with ritonavir; in the other trial, saquinavir was administered as single drug. The INVIRASE tablet and the saquinavir mesylate capsule (hard gel) were similarly tolerated. The most common adverse events were gastrointestinal disorders (nausea, vomiting, and diarrhea). Similar bioavailability was demonstrated and no clinically significant differences in saquinavir exposures were seen. Thus, similar safety profiles are expected between the two INVIRASE formulations.

A study investigating the drug-drug interaction of rifampin 600 mg/day daily and INVIRASE 1000 mg/ritonavir 100 mg twice daily enrolled 28 healthy volunteers. Eleven of 17 (65%) healthy volunteers exposed concomitantly to rifampin and INVIRASE/ritonavir developed severe hepatocellular toxicity which presented as increased hepatic transaminases. In some subjects, transaminases increased up to > 20-fold the upper limit of normal and were associated with gastrointestinal symptoms, including abdominal pain, gastritis, nausea, and vomiting. Following discontinuation of all three drugs, clinical symptoms abated and hepatic transaminases normalized [see CONTRAINDICATIONS].

Additional Adverse Reactions Reported During Clinical Trials with Saquinavir

Blood and lymphatic system disorders: anemia, hemolytic anemia, leukopenia, lymphadenopathy, neutropenia, pancytopenia, thrombocytopenia

Cardiac disorders: heart murmur, syncope

Ear and labyrinth disorders: tinnitus

Eye disorders: visual impairment

Gastrointestinal disorders: abdominal discomfort, ascites, dyspepsia, dysphagia, eructation, flatulence, gastritis, gastrointestinal hemorrhage, intestinal obstruction, mouth dry, mucosal ulceration, pancreatitis

General disorders and administration site conditions: anorexia, asthenia, chest pain, edema, lethargy, wasting syndrome, weight increased

Hepatobiliary disorders: chronic active hepatitis, hepatitis, hepatomegaly, hyperbilirubinemia, jaundice, portal hypertension

Immune system disorders: allergic reaction

Investigations: ALT increase, AST increase, blood creatine phosphokinase increased, increased alkaline phosphatase, GGT increase, raised amylase, raised LDH

Metabolism and nutrition disorders: increased or decreased appetite, dehydration, hypertriglyceridemia

Musculoskeletal and connective tissue disorders: arthralgia, muscle spasms, myalgia, polyarthritis

Neoplasms benign, malignant and unspecified (including cysts and polyps): acute myeloid leukemia, papillomatosis

Nervous system disorders: confusion, convulsions, coordination abnormal, dizziness, dysgeusia, headache, hypoesthesia, intracranial hemorrhage leading to death, loss of consciousness, paresthesia, peripheral neuropathy, somnolence, tremor

Psychiatric disorders: anxiety, depression, insomnia, libido disorder, psychotic disorder, sleep disorder, suicide attempt

Renal and urinary disorders: nephrolithiasis

Respiratory, thoracic and mediastinal disorders: cough, dyspnea

Skin and subcutaneous tissue disorders: acne, alopecia, dermatitis bullous, drug eruption, erythema, severe cutaneous reaction associated with increased liver function tests, Stevens-Johnson syndrome, sweating increased, urticaria

Vascular disorders: hypertension, hypotension, thrombophlebitis, peripheral vasoconstriction

Clinical Trial Experience In Pediatric Subjects

Limited safety data are available from two pediatric clinical trials of saquinavir mesylate capsules (hard gel) (approximately 50 mg per kg twice daily) used in combination with either low dose ritonavir or lopinavir/ritonavir. These trials enrolled pediatric subjects aged 4 months to 16 years old. In the HIVNAT 017 study (saquinavir mesylate capsules (hard gel) + lopinavir/ritonavir), adverse events were reported in 90% of the 50 subjects enrolled. The most commonly reported adverse events considered related to study treatment were diarrhea (18%) and vomiting (10%). In the NV20911 study (saquinavir mesylate capsules (hard gel) + ritonavir), 4 subjects (22% of 18 enrolled) experienced adverse events that were considered related to INVIRASE + ritonavir. These events (n) were vomiting (3), abdominal pain (1) and diarrhea (1). All reported adverse events were mild or moderate in intensity. The adverse reaction profile of INVIRASE in the pediatric trials is similar to that observed in adult trials.

Postmarketing Experience

Additional adverse events identified during postmarketing use are similar to those observed in clinical trials with INVIRASE, saquinavir mesylate capsules (hard gel and soft gel) alone or in combination with ritonavir. Because these events are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to INVIRASE exposure. In addition, torsade de pointes has been reported rarely [see WARNINGS AND PRECAUTIONS].

Read the entire FDA prescribing information for Invirase (Saquinavir Mesylate)

© Invirase Patient Information is supplied by Cerner Multum, Inc. and Invirase Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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