Drug Interactions between Hismanal and idelalisib
This report displays the potential drug interactions for the following 2 drugs:
- Hismanal (astemizole)
- idelalisib
Interactions between your drugs
astemizole idelalisib
Applies to: Hismanal (astemizole) and idelalisib
GENERALLY AVOID: Coadministration with idelalisib may increase the plasma concentrations of drugs that are substrates of CYP450 3A4. Idelalisib has been shown to be a potent inhibitor of this isoenzyme. In healthy volunteers, administration of a single 5 mg dose of midazolam, a CYP450 3A4 probe substrate, with idelalisib 150 mg for 15 doses increased mean midazolam peak plasma concentration (Cmax) by 2.4-fold and systemic exposure (AUC) by 5.4-fold.
MANAGEMENT: Use of idelalisib should generally be avoided with drugs that are primarily metabolized by CYP450 3A4, particularly those with a narrow therapeutic range (e.g., antiarrhythmics, anticonvulsants, antineoplastics, immunosuppressants) or those that are considered sensitive substrates (e.g., ergot derivatives, statins, oral midazolam, triazolam). Dosage adjustments as well as clinical and laboratory monitoring may be appropriate for some drugs whenever idelalisib is added to or withdrawn from therapy, if coadministration is required.
References (1)
- (2014) "Product Information. Zydelig (idelalisib)." Gilead Sciences
Drug and food interactions
astemizole food
Applies to: Hismanal (astemizole)
GENERALLY AVOID: Some beverages such as tonic water contain varying amounts of quinine. Coadministration of a single 430 mg dose of quinine has been shown to increase plasma concentrations of astemizole and its metabolite, desmethylastemizole. Elevated levels of these agents may cause a prolongation of the electrocardiographic QT interval and potentially fatal ventricular arrhythmias. Although pharmacokinetic data have indicated that the amounts of quinine in beverages (up to 80 mg quinine in 32 oz of tonic water) are not sufficient to produce a significant effect, the potential for an interaction exists if large amounts of tonic water are ingested. Also, grapefruit juice has been shown to inhibit CYP450 enzymes, which may lead to increased serum astemizole concentrations. The risk of life-threatening ventricular arrhythmias may be increased.
MANAGEMENT: Patients should be counseled to limit consumption of quinine-containing beverages and avoid grapefruit juice while they are taking astemizole.
References (1)
- (2002) "Product Information. Hismanal (astemizole)." Janssen Pharmaceuticals
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.
Check Interactions
To view an interaction report containing 4 (or more) medications, please sign in or create an account.
Save Interactions List
Sign in to your account to save this drug interaction list.