Fosamprenavir and Rescriptor

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Using delavirdine together with fosamprenavir is not recommended. Combining these medications can alter the blood levels and effects of both medications. Specifically, delavirdine levels may decrease, which may make the medication less effective in treating HIV infection. At the same time, fosamprenavir levels may increase, and you may experience more frequent and/or severe side effects such as diarrhea, rash, nausea, vomiting, increased blood sugar, and increased cholesterol or triglycerides. Your doctor may be able to prescribe alternatives that do not interact. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

CONTRAINDICATED: Coadministration with amprenavir or its prodrug, fosamprenavir, may significantly decrease the plasma concentrations of delavirdine. The exact mechanism of interaction has not been established. Conversely, delavirdine may increase the plasma concentrations of amprenavir by inhibiting CYP450 3A4 metabolism. In 9 subjects treated with delavirdine and amprenavir, both at 600 mg twice a day for 10 days, delavirdine peak plasma concentration (Cmax), systemic exposure (AUC) and trough plasma concentration (Cmin) decreased by 47%, 61% and 88%, respectively, while the same values for amprenavir increased by 40%, 130% and 125%, respectively, compared to either drug administered alone. In another study, 11 healthy volunteers given delavirdine and amprenavir 600 mg each twice a day for 7 days achieved higher levels of amprenavir Cmax, AUC and Cmin by 18%, 30% and 90%, respectively, than when given amprenavir alone at 1200 mg twice a day. Delavirdine Cmax, AUC and Cmin decreased by 30%, 50% and 70%, respectively.

MANAGEMENT: Given the risk of reduced viral susceptibility and resistance development associated with subtherapeutic antiretroviral drug levels, concomitant use of delavirdine with amprenavir or fosamprenavir is considered contraindicated.

Fosamprenavir

Generic Name: fosamprenavir

Brand name: Lexiva, Telzir

Synonyms: n.a.

What is Fosamprenavir?

Rescriptor

Generic Name: delavirdine

Brand name: Rescriptor

Synonyms: n.a.

What is Rescriptor?