Skip to main content

Drug Interactions between astemizole and erdafitinib

This report displays the potential drug interactions for the following 2 drugs:

Edit list (add/remove drugs)

Interactions between your drugs

Moderate

astemizole erdafitinib

Applies to: astemizole and erdafitinib

GENERALLY AVOID: Coadministration with erdafitinib may alter the plasma concentrations of drugs that are substrates of the CYP450 3A4 isoenzyme, resulting in increased toxicity or decreased efficacy of these drugs. In vitro, erdafitinib has been shown to be a time-dependent inhibitor as well as inducer of CYP450 3A4. However, no pharmacokinetic data are available from drug interaction studies.

MANAGEMENT: Concomitant use of erdafitinib and sensitive CYP450 3A4 substrates or substrates with narrow therapeutic ranges should generally be avoided.

References (1)
  1. (2019) "Product Information. Balversa (erdafitinib)." Janssen Products, LP

Drug and food interactions

Major

astemizole food

Applies to: 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)
  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

Report options

Loading...
QR code containing a link to this page

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor 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.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer