CRIXIVAN
General description

Crixivan is the brand name for the drug indinavir sulfate prduced by Merck and Co., Inc. It is an inhibitor of HIV protease available as an orally administered capsule.

Mechanism

Indinavir binds to the portease active site of HIV protease and inhibits the enzyme activity. This prevents cleavage of viral polyproteins resulting the the formation of immature noninfectious viral particles.

Indications

Crixivan is indicated in combination with other antiretroviral agenst as treatment for HIV infection.

Usage/Dosage

Recommended dosage is 800 mg every 8 hours in the form of 2 400 mg capsules. It should be adminstered without food, but wiht water 1 hour before or two hours after a meal to maximize absorption. It can be concomitantly adminstered with rifabutin, ketoconazole, didanosine. With rifabutin, Crixivan dosage should be increased to 1000 mg every eight hours while rifabutin dosage should be halved. While coadministering with ketoconazole, Crixivan dosage should be reduced to 600 mg every 8 hours, and if coadministered with didanosine, they whould be taken at least one hour apart on an emply stomach.

Precautions

Patients should be told that Crixivan is not a cure for HIV infection and they may continue to develop illnesses associated with the progression of HIV disease. Crixivan is known to interact with rifabutin, ketoconazole, and didanosine. Administration should be altered accordingly. Crixivan should not be adminstered with rifampin.

Contraindications

Crixivan is contraindicated for patients with clinically significant hypersensitivity to any of its components and should not be adminstered concurrently with rifampin, terfenadine, cisapride, astemizole, triazolam, midazolam, or ergot derivatives.

Potential Adverse Effects

In about 9% of cases, nephrolithiasis, inculding flank pain has been reported. Not very many common side effects have been shown.