Indinavir: Potent Protease Inhibition for HIV Management
Indinavir
| Product dosage: 400 mg | |||
|---|---|---|---|
| Package (num) | Per cap | Price | Buy |
| 30 | 4.80 $ | 143.91 $ (0%) | 🛒 Add to cart |
| 60 | 3.65 $
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Synonyms | |||
Indinavir is a protease inhibitor antiretroviral medication indicated for the treatment of human immunodeficiency virus (HIV-1) infection. It functions by selectively binding to the active site of the HIV-1 protease enzyme, thereby preventing the cleavage of viral polyprotein precursors into functional proteins required for viral replication. This agent is typically administered in combination with other antiretroviral agents as part of a highly active antiretroviral therapy (HAART) regimen, aimed at reducing viral load, increasing CD4 cell counts, and delaying the progression to acquired immunodeficiency syndrome (AIDS). Proper adherence to dosing schedules and dietary recommendations is critical to maintaining therapeutic drug levels and minimizing resistance development.
Features
- Active pharmaceutical ingredient: Indinavir sulfate
- Standard formulation: 200 mg, 333 mg, and 400 mg capsules
- Mechanism: Selective inhibition of HIV-1 protease
- Pharmacokinetics: Rapid absorption with peak plasma concentrations within 1 hour
- Administration: Oral route with specific hydration and dietary requirements
- Metabolism: Hepatic, primarily via CYP3A4 isoenzyme
- Excretion: Renal and fecal pathways
Benefits
- Effectively reduces HIV-1 viral load in plasma when used in combination therapy
- Contributes to immunologic restoration as evidenced by increased CD4+ T-cell counts
- Delays disease progression and reduces the incidence of opportunistic infections
- May improve overall survival rates in appropriately selected patient populations
- Supports long-term viral suppression when adherence to regimen is maintained
- Provides a treatment option within structured antiretroviral therapy protocols
Common use
Indinavir is principally utilized as a component of combination antiretroviral therapy for the management of HIV-1 infection in adults and pediatric patients over 4 years of age. It is indicated for both treatment-naïve and treatment-experienced individuals, though resistance patterns should guide therapeutic decisions. Clinical use is predicated on virologic, immunologic, and clinical criteria as established by current treatment guidelines. The medication is not recommended as monotherapy due to the high risk of rapid resistance development.
Dosage and direction
The recommended adult dosage is 800 mg administered orally every 8 hours. For optimal absorption, indinavir must be taken either 1 hour before or 2 hours after a meal, though it may be administered with a light, low-fat snack if necessary. Adequate hydration (at least 1.5 liters daily) is essential to reduce the risk of nephrolithiasis. Dosage adjustments are required in patients with hepatic impairment, and concomitant administration with certain medications may necessitate modification of the indinavir dosing regimen. Pediatric dosing is based on body surface area or weight, with specific protocols detailed in prescribing information.
Precautions
Patients should be monitored for signs of nephrolithiasis, including flank pain and hematuria. Hepatic function should be assessed periodically, as transaminase elevations may occur. Consider monitoring blood glucose levels due to potential hyperglycemia and diabetes mellitus development. Lipid profiles should be evaluated at baseline and during treatment, as dyslipidemia has been observed. Caution is advised in patients with hemophilia due to increased bleeding risk. Adequate contraceptive measures are recommended, as indinavir may reduce the efficacy of oral contraceptives.
Contraindications
Indinavir is contraindicated in patients with known hypersensitivity to indinavir or any component of the formulation. Concomitant administration with drugs highly dependent on CYP3A4 for clearance and with narrow therapeutic indices is contraindicated, including alfuzosin, amiodarone, ergot derivatives, lovastatin, simvastatin, pimozide, sildenafil (for pulmonary arterial hypertension), triazolam, and oral midazolam. It is also contraindicated with drugs that strongly induce CYP3A4 and may reduce indinavir concentrations to subtherapeutic levels.
Possible side effect
Common adverse reactions include nephrolithiasis/urolithiasis (approximately 12% of patients), nausea, abdominal pain, vomiting, diarrhea, headache, insomnia, dizziness, blurred vision, rash, and taste perversion. Laboratory abnormalities may include hyperbilirubinemia (14%), asymptomatic hyperglycemia, elevated transaminases, and lipid abnormalities. Less frequently reported effects include thrombocytopenia, hemolytic anemia, and cases of acute hemolytic anemia. Some patients may experience body fat redistribution and metabolic disorders associated with protease inhibitor therapy.
Drug interaction
Indinavir is a substrate and inhibitor of CYP3A4, resulting in numerous potential interactions. Coadministration with rifampin, rifabutin, St. John’s wort, or anticonvulsants may significantly decrease indinavir concentrations. Conversely, indinavir may increase concentrations of calcium channel blockers, immunosuppressants, and other CYP3A4 substrates. Dose adjustments are required with rifabutin (reduce rifabutin dose by 50%) and ketoconazole (reduce indinavir dose to 600 mg every 8 hours). Didanosine should be administered at least 1 hour apart due to gastric pH considerations.
Missed dose
If a dose is missed within 2 hours of the scheduled time, the patient should take the missed dose immediately and resume the regular dosing schedule. If more than 2 hours have passed, the missed dose should be skipped and the next dose taken at the regularly scheduled time. Patients should not double the dose to make up for a missed administration. Consistent adherence to the dosing schedule is critical to maintain effective viral suppression and prevent resistance development.
Overdose
There is limited experience with indinavir overdose. Reported cases have included nephrolithiasis and flank pain with doses up to 2.4 grams every 8 hours. There is no specific antidote for indinavir overdose. Management should consist of general supportive measures, including maintenance of hydration to promote renal excretion and monitoring of vital signs. Hemodialysis is unlikely to be beneficial due to extensive protein binding and large volume of distribution. Contact a poison control center for current guidance on management.
Storage
Store capsules at controlled room temperature 20°C to 25°C (68°F to 77°F), with excursions permitted between 15°C and 30°C (59°F and 86°F). Keep in the original container with the cap tightly closed to protect from moisture. Dispense in a tight container if original packaging is compromised. Do not use beyond the expiration date printed on the packaging. Keep out of reach of children and pets.
Disclaimer
This information is provided for educational purposes only and does not constitute medical advice. Treatment decisions should be made by qualified healthcare professionals based on individual patient characteristics and current treatment guidelines. The prescribing physician should be consulted for complete information regarding indications, dosing, warnings, and precautions. Actual clinical outcomes may vary based on individual patient factors and adherence to prescribed regimens.
Reviews
Clinical trials have demonstrated that indinavir, in combination with other antiretroviral agents, produces significant reductions in viral load and increases in CD4 cell counts. In study ACTG 320, the triple combination of indinavir, zidovudine, and lamivudine reduced the risk of AIDS-defining illness or death by 50% compared to two-drug therapy alone. Longer-term follow-up has confirmed sustained virologic suppression in adherent patients, though resistance patterns have emerged with suboptimal adherence. Real-world evidence supports its efficacy within structured treatment protocols, though newer agents with improved tolerability profiles have largely superseded indinavir in contemporary practice.