Tagrisso vs. Iressa

Are Tagrisso and Iressa the Same Thing?

Tagrisso (osimertinib) and Iressa (gefitinib) are kinase inhibitors used to treat patients with non-small cell lung cancer (NSCLC).

Side effects of Tagrisso and Iressa that are similar include diarrhea, skin reactions (rash, dry skin, itching), nail disorders, decreased appetite, inflammation of the mouth and lips, and eye disorders (eyelid swelling, dry eye).

Side effects of Tagrisso that are different from Iressa include nausea, constipation, cough, fatigue, back pain, headache, pneumonia, and blood clots.

Side effects of Iressa that are different from Tagrisso include vomiting.

Both Tagrisso and Iressa may interact with antifungals, rifampicin, and phenytoin.

Tagrisso may also interact with macrolide antibiotics, antivirals, nefazodone, St. John's wWort, fentanyl, cyclosporine, quinidine, ergot alkaloids, and carbamazepine.

Iressa may also interact with tricyclic antidepressants, proton pump inhibitors (PPIs), histamine H2-receptor antagonists, antacids, and warfarin.

What Are Possible Side Effects of Tagrisso?

Side effects of Tagrisso include

  • diarrhea,
  • rash,
  • dry skin,
  • nail toxicity,
  • nausea,
  • decreased appetite,
  • constipation,
  • inflammation of the mouth and lips,
  • itching,
  • eye disorders,
  • cough,
  • fatigue,
  • back pain,
  • headache,
  • pneumonia, and
  • blood clots.

What Are Possible Side Effects of Iressa?

Common side effects of Iressa include:

  • skin reactions,
  • nail disorders,
  • diarrhea,
  • vomiting,
  • inflammation of the mouth lining,
  • decreased appetite,
  • eyelid swelling, and
  • dry eye.

Tell your doctor if you have unlikely but serious side effects of Iressa including:

What Is Tagrisso?

Tagrisso (osimertinib) is a kinase inhibitor indicated for the treatment of patients with metastatic epidermal growth factor receptor (EGFR) T790M mutation-positive non-small cell lung cancer (NSCLC), as detected by an FDA-approved test, who have progressed on or after EGFR TKI therapy.

What Is Iressa?

Iressa (gefitinib) is a tyrosine kinase inhibitor used for the first-line treatment of patients with metastatic non-small cell lung cancer (NSCLC) whose tumors have epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 (L858R) substitution mutations as detected by an FDA-approved test.


Lung Cancer: Early Signs, Symptoms, Stages See Slideshow

What Drugs Interact With Tagrisso?

Tagrisso may interact with macrolide antibiotics, antifungals, antivirals, nefazodone, phenytoin, rifampicin, St. John's Wort, fentanyl, cyclosporine, quinidine, ergot alkaloids, and carbamazepine. Tell your doctor all medications and supplements you use. Tagrisso is not recommended for use during pregnancy; it may harm a fetus. Breastfeeding is not recommended during treatment with Tagrisso.

What Drugs Interact With Iressa?

Iressa may interact with rifampicin, phenytoin, tricyclic antidepressants, azole antifungals, proton pump inhibitors (PPIs), histamine H2-receptor antagonists, antacids, and warfarin.

How Should Tagrisso Be Taken?

The dose of Tagrisso is 80 mg orally once daily, with or without food.

How Should Iressa be Taken?

The recommended dose of Iressa is 250 mg orally, once daily with or without food.


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AstraZeneca. Tagrisso Product Information.


AstraZeneca. Iressa Product Information


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