Gefitinib

Name: Gefitinib Drug Interactions
Creator: Dr. Brian Staiger, PharmD, BCPS

60 interactions 147 cited references

Also sold as: Iressa Iressa®

About Gefitinib

Gefitinib is used to treat non-small cell lung cancer that has spread to other parts of the body in people with certain types of tumors. Gefitinib is in a class of medications called kinase inhibitors. It works by blocking the action of a certain naturally occurring substance that may be needed to help cancer cells mul… Read the full Gefitinib drug information page →

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Aug 9, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Typhoid Vaccine Measles Virus Vaccine, Live Smallpox Monkeypox Vaccine Mavorixafor Rubella Virus Vaccine, Live Yellow Fever Vaccine

10 Contraindicated 48 Major 2 Moderate

All (60) Contraindicated (10) Major (48) Moderate (2)

Moderate

Gefitinib Levothyroxine Ermeza Increased risk of hypothyroidism Details Gefitinib Warfarin Coumadin Increased prothrombin time and INR values and an increased risk of bleeding Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.