Skip to main content

Drug Interactions between lapatinib and lazertinib

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

Edit list (add/remove drugs)

Interactions between your drugs

Moderate

lapatinib lazertinib

Applies to: lapatinib and lazertinib

MONITOR: Coadministration with inhibitors of CYP450 3A4 may increase the plasma concentrations of lapatinib, which is primarily metabolized by the isoenzyme. In healthy subjects, administration of lapatinib in combination with the potent inhibitor ketoconazole (200 mg twice daily for 7 days) resulted in lapatinib systemic exposure (AUC) and half-life that were approximately 3.6- and 1.7-fold, respectively, of the control values.

MANAGEMENT: Caution is advised when lapatinib is prescribed with CYP450 3A4 inhibitors. Pharmacologic response to lapatinib should be monitored more closely whenever a CYP450 3A4 inhibitor is added to or withdrawn from therapy, and the lapatinib dosage adjusted as necessary. Patients should be advised to contact their physician if they experience increased adverse effects of lapatinib such as diarrhea, nausea, vomiting, dyspepsia, and fatigue.

References (1)
  1. (2007) "Product Information. Tykerb (lapatinib)." Novartis Pharmaceuticals

Drug and food interactions

Moderate

lapatinib food

Applies to: lapatinib

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of lapatinib. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits.

ADJUST DOSING INTERVAL: Food can significantly increase the oral bioavailability of lapatinib. According to the manufacturer, lapatinib peak plasma concentration (Cmax) was approximately 2.5- and 3-fold higher and systemic exposure (AUC) 3- and 4-fold higher when administered with a low fat meal (5% fat; 500 calories) or with a high-fat meal (50% fat; 1000 calories), respectively, compared to fasting. Dividing the daily dose also resulted in an approximately 2-fold higher systemic exposure at steady state compared to the same total dose administered once daily.

MANAGEMENT: Patients treated with lapatinib should preferably avoid the consumption of grapefruit or grapefruit juice. The manufacturer recommends that lapatinib be administered at least one hour before or one hour after a meal. The lapatinib dose is administered once daily and should not be divided.

References (1)
  1. (2007) "Product Information. Tykerb (lapatinib)." Novartis Pharmaceuticals

Therapeutic duplication warnings

Therapeutic duplication is the use of more than one medicine from the same drug category or therapeutic class to treat the same condition. This can be intentional in cases where drugs with similar actions are used together for demonstrated therapeutic benefit. It can also be unintentional in cases where a patient has been treated by more than one doctor, or had prescriptions filled at more than one pharmacy, and can have potentially adverse consequences.

Duplication

Egfr inhibitors

Therapeutic duplication

The recommended maximum number of medicines in the 'EGFR inhibitors' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'EGFR inhibitors' category:

  • lapatinib
  • lazertinib

Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.


Report options

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.