Afatinib is an oral tyrosine kinase inhibitor used to treat certain types of non-small cell lung cancer. The following briefly introduces its dosage and administration, efficacy, and precautions from three aspects.

I. Dosage and Administration

1. Recommended Dose

The starting dose is 40 mg once daily, taken orally.

It should be taken on an empty stomach, that is, at least 1 hour before meals or at least 2 hours after meals.

Take the medication at a fixed time every day, swallow the tablet whole, and do not crush or chew it.

2. Dose Adjustment

If severe adverse reactions occur, the dose may be reduced to 30 mg daily, and further reduced to 20 mg daily if necessary.

If it is still not tolerated, treatment should be permanently discontinued.

If a dose is missed, it may be taken if more than 12 hours remain before the next scheduled dose; otherwise, skip it and do not double the dose.

II. Efficacy

1. Indications

It is used for first-line treatment of metastatic non-small cell lung cancer (NSCLC) with positive EGFR mutations.

It is also used for patients with squamous NSCLC that has progressed after platinum-containing chemotherapy.

2. Efficacy Characteristics

For patients with EGFR-sensitive mutations, it can significantly prolong progression-free survival.

It also has good efficacy against some rare EGFR mutations.

Efficacy varies depending on the mutation type and individual differences, and genetic testing is required to confirm the eligible population.

III. Precautions

1. Common Adverse Reactions

Diarrhea, rash, stomatitis, paronychia, and decreased appetite.

Diarrhea is relatively common, and if severe, fluid replacement should be given promptly and medical attention should be sought.

2. Serious Adverse Reactions

Interstitial lung disease may occur, and medical attention should be sought immediately if dyspnea, cough, or fever occurs.

Severe diarrhea, dehydration, and abnormal liver and kidney function may occur.

Liver function, kidney function, and complete blood count should be monitored regularly.

3. Contraindications and Cautions

It is contraindicated in patients allergic to this product.

It should be used with caution in pregnant and breastfeeding women, and women of childbearing age should use contraception during treatment.

It should be used with caution in patients with severe hepatic impairment.

4. Drug Interactions

Avoid concomitant use with strong CYP3A4 inducers or inhibitors.

Concomitant use with P-gp inhibitors may increase exposure to this product, and dose adjustment is required.

Patients should inform their doctor of all concomitant medications during treatment.

5. Patient Education

Strictly follow the doctor's instructions when taking the medication, and do not increase, decrease, or stop the dose on your own.

If severe or persistent adverse reactions occur, contact the doctor promptly.

Attend regular follow-up visits and cooperate with genetic testing and imaging evaluations.