Indinavir / Crixivan
Indinavir, marketed under the brand name Crixivan, is a medication used in the treatment of Human Immunodeficiency Virus (HIV) infection. It belongs to a class of drugs known as protease inhibitors, which play a crucial role in the management of HIV by preventing the virus from multiplying in the body.
Mechanism of Action
Indinavir works by inhibiting the action of the HIV protease enzyme. This enzyme is essential for the virus to replicate and produce new viral particles. By blocking protease, Indinavir prevents the cleavage of viral polyproteins, resulting in the production of immature, non-infectious viral particles. This action helps to reduce the viral load in the body, thereby slowing the progression of HIV infection and improving immune function.
Usage and Administration
Indinavir is typically prescribed as part of a combination antiretroviral therapy (ART) regimen. It is important to use it in conjunction with other antiretroviral medications to enhance its effectiveness and reduce the risk of developing drug resistance. The standard dosage of Indinavir is 800 mg taken every eight hours. It is crucial to adhere to the prescribed schedule to maintain consistent drug levels in the bloodstream.
Important Administration Tips
- Indinavir should be taken on an empty stomach, at least one hour before or two hours after a meal, to ensure optimal absorption.
- Patients should drink plenty of water throughout the day to prevent kidney stones, a potential side effect of Indinavir.
- It is important to avoid high-fat meals when taking Indinavir, as they can reduce the drug's absorption.
Side Effects
Like all medications, Indinavir can cause side effects. While some individuals may experience mild side effects, others may encounter more severe reactions. Common side effects include:
- Nausea
- Diarrhea
- Headache
- Fatigue
- Abdominal pain
More serious side effects, although less common, may include:
- Kidney stones
- Hyperbilirubinemia (increased bilirubin levels in the blood)
- Lipodystrophy (changes in body fat distribution)
- Increased blood sugar levels
Patients should promptly report any unusual or severe side effects to their healthcare provider.
Drug Interactions
Indinavir can interact with several other medications, which may affect its efficacy or increase the risk of adverse effects. Some notable interactions include:
- Rifampin: This antibiotic can significantly reduce Indinavir levels, making it less effective.
- St. John's Wort: An herbal supplement that can decrease Indinavir concentrations.
- Other Protease Inhibitors: Combining Indinavir with other protease inhibitors may require dosage adjustments.
Patients should inform their healthcare provider of all medications, supplements, and herbal products they are taking to avoid potential interactions.
Special Considerations
Pregnancy and Breastfeeding
Indinavir should be used during pregnancy only if the potential benefits justify the potential risks to the fetus. Pregnant women with HIV are encouraged to discuss treatment options with their healthcare provider to ensure the best outcomes for both mother and child. Breastfeeding is not recommended for HIV-positive mothers to prevent transmission of the virus to the infant.
Resistance and Adherence
Adherence to the prescribed treatment regimen is critical to prevent the development of drug-resistant strains of HIV. Patients should take Indinavir exactly as directed and avoid missing doses. If a dose is missed, it should be taken as soon as possible unless it is almost time for the next dose.
Articles/Studies
St. John’s wortmay interact with Indinavir causing decreased drug effectiveness and worsening of HIV infection by lowering blood levels of the drug. Indinavir concentrations and St John’s wort.
Milk thistle and indinavir: a randomized controlled pharmacokinetics study and meta-analysis
Edwards DJ. Influence of goldenseal root on the pharmacokinetics of indinavir