This page contains brief details about the drug , it's indication, dosage & administaration, mechanism of action, related brands with strength, warnings and common side effects.

Background and Date of Approval

Lapatinib was approved for the first time on Mar 13, 2007, by the U.S. FDA in combination with Capecitabine for treating advanced or metastatic breast cancer in women.

Mechanism of Action of undefined

Lapatinib acts against the enzyme called tyrosine kinase. It prevents the Human epidermal growth factor receptor protein (HER2) and Epidermal growth factor receptors (EGFRs) from signaling, which breast cancer cells produce. It kills cancer cells and slows down their growth.

Uses of undefined

Lapatinib is used to treat advanced or HER2 Positive metastatic breast cancer.

undefined Drug administaration and Dosage available

Lapatinib is available as a tablet and used in combination with Capecitabine. The recommended dose is 1,250 mg (5 tablets of Lapatinib 250 mg) given orally once daily on days 1 to 21. It is advisable to take it before or after taking the food. Swallow the tablet and do not crush, open, or dissolve them. Your doctor may advise you to temporarily reduce your dose or discontinue your therapy.

Warnings, Precautions and Side Effects of undefined


Notify your healthcare provider at the first sign of diarrhea or dehydration. Monitor your blood pressure regularly while taking this medication. If you notice a severe headache, confusion, vomiting, or vomiting, report to your doctor. Tell your doctor about inflammation of the lungs, liver, and kidney problems.


Discuss the contraceptive options with your doctor before starting this treatment if there is a possibility that you may become pregnant. Use contraceptive methods during and five days after completing this treatment. Avoid breastfeeding during and five days after finishing this treatment course. If Lapatinib passes into breast milk is unknown.

Side Effects

The common side effects that are likely to occur while you are on the treatment with Lapatinib are nausea, vomiting, tiredness, weakness, itching, dry skin, loss of appetite, indigestion, constipation, mouth ulcers, stomach pain, difficulty in sleeping, joint or back pain, cough, breathing problems, headache, etc. If you experience severe allergic reactions, skin rashes, heart, liver, and lung problems, report your physician immediately.

Word Of Advice

Lapatinib can cause severe diarrhea, so it is advised to take plenty of water during the treatment. Eat a well-balanced diet. Avoid consuming grapefruit juice while on therapy with Lapatinib as it affects how the medicine works. This medication makes your skin sensitive to the sun and increases your risk of skin rashes. Avoid spending more time in the sunlight, and ensure that you always apply sunscreen with a good SPF before stepping out. Wash your skin with a soap-free cleanser. Take special care while driving or operating machines during this treatment as it may impair your ability.

Frequently Asked Question


  1. Novartis Europharm Limited, Electronic medicines compendium (EMC), [ Revised on March 2022] [ Accessed on 19th August 2022],
  2. GlaxoSmithKline, US Food & Drug Administration, [ Accessed on 19th August 2022],
  3. Edward Chu, Cancer Chemotherapy, Lange’s Basic and Clinical Pharmacology, 14th Edition, 2018, 948-976.
  4. KD Tripathi, Anticancer Drugs, Essentials of Medical Pharmacology, 8th Edition, 2019, 915-936.


The drug information on this page is not a substitute for medical advice; it is meant for educational purposes only. For further details, consult your doctor about your medical condition to know if you are eligible to receive this treatment.