Drug Interactions between saquinavir and Tracleer
This report displays the potential drug interactions for the following 2 drugs:
- saquinavir
- Tracleer (bosentan)
Interactions between your drugs
saquinavir bosentan
Applies to: saquinavir and Tracleer (bosentan)
ADJUST DOSE: Coadministration of a protease inhibitor (PI) in combination with bosentan may increase the plasma concentration of bosentan and decrease that of the PI, unless ritonavir is included as a pharmacokinetic booster. Both PIs and bosentan are primarily metabolized by CYP450 3A4. Because PIs are also inhibitors of CYP450 3A4, they can inhibit the metabolic clearance of bosentan. Conversely, bosentan may induce the metabolism of PIs, although the effects are probably not significant in the presence of ritonavir, which is a potent CYP450 3A4 inhibitor.
MANAGEMENT: Protease inhibitors should generally not be used in combination with bosentan unless ritonavir is also added as a pharmacokinetic booster. Dose adjustment of bosentan has been recommended. In patients who are starting bosentan and have been receiving PI therapy for at least 10 days, it has been recommended to start bosentan at 62.5 mg once daily or every other day based upon individual tolerability. When starting PI therapy in patients already on bosentan, it has been recommended to discontinue bosentan for at least 36 hours prior to initiation of PI therapy. After at least 10 days following the initiation of PI therapy, bosentan may be resumed at 62.5 mg once daily or every other day based upon individual tolerability. According to some authorities, use of the fixed combination atazanavir-cobicistat with bosentan is not recommended.
References (11)
- (2001) "Product Information. Invirase (saquinavir)." Roche Laboratories
- (2001) "Product Information. Crixivan (indinavir)." Merck & Co., Inc
- (2001) "Product Information. Viracept (nelfinavir)." Agouron Pharma Inc
- (2001) "Product Information. Kaletra (lopinavir-ritonavir)." Abbott Pharmaceutical
- (2003) "Product Information. Reyataz (atazanavir)." Bristol-Myers Squibb
- (2003) "Product Information. Lexiva (fosamprenavir)." GlaxoSmithKline
- (2005) "Product Information. Aptivus (tipranavir)." Boehringer-Ingelheim
- Cerner Multum, Inc. "UK Summary of Product Characteristics."
- (2006) "Product Information. Prezista (darunavir)." Ortho Biotech Inc
- Cerner Multum, Inc. "Australian Product Information."
- (2015) "Product Information. Evotaz (atazanavir-cobicistat)." Bristol-Myers Squibb
Drug and food interactions
saquinavir food
Applies to: saquinavir
ADJUST DOSING INTERVAL: Food significantly increases the absorption of saquinavir.
MONITOR: Coadministration with grapefruit juice may increase the plasma concentrations of saquinavir. The primary mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits. In eight healthy volunteers, ingestion of 400 mL of grapefruit juice prior to administration of a 600 mg dose of saquinavir mesylate increased the area under the plasma concentration-time curve and oral bioavailability of saquinavir by 50% and 100%, respectively, compared to water; however, the increase is not considered clinically relevant. A high degree of intersubject variability in the grapefruit juice effect was also observed. The extent to which this interaction may occur with the saquinavir free base soft gelatin capsule is unknown. However, the saquinavir soft gelatin capsule formulation is no longer commercially available.
MANAGEMENT: Saquinavir mesylate should be taken with meals or within 2 hours after eating to enhance bioavailability. Patients should be advised to avoid the consumption of large amounts of grapefruit and grapefruit juice during saquinavir therapy unless otherwise directed by their doctor, as the interaction is unreliable and subject to a high degree of interpatient variation.
References (6)
- (2001) "Product Information. Invirase (saquinavir)." Roche Laboratories
- Kupferschmidt HHT, Fattinger KE, Ha HR, Follath F, Krahenbuhl S (1998) "Grapefruit juice enhances the bioavailability of the HIV protease inhibitor saquinavir in man." Br J Clin Pharmacol, 45, p. 355-9
- Bailey DG, Malcolm J, Arnold O, Spence JD (1998) "Grapefruit juice-drug interactions." Br J Clin Pharmacol, 46, p. 101-10
- Eagling VA, Profit L, Back DJ (1999) "Inhibition of the CYP3A4-mediated metabolism and P-glycoprotein-mediated transport of the HIV-I protease inhibitor saquinavir by grapefruit juice components." Br J Clin Pharmacol, 48, p. 543-52
- Cerner Multum, Inc. "UK Summary of Product Characteristics."
- Cerner Multum, Inc. "Australian Product Information."
Therapeutic duplication warnings
No warnings were found for your selected drugs.
Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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