Dacomitinib, as an EGFR inhibitor, has specific contraindications, dietary restrictions, and medication constraints that must be strictly followed to avoid serious adverse reactions. The following provides a detailed explanation from three aspects: classification of taboo groups, list of taboo foods, and special restrictions.

1. Taboo population

(1) Pregnant women: Animal studies have shown embryonic toxicity and may cause fetal malformations. It is necessary to confirm the pregnancy status before medication and take effective contraceptive measures.

(2) Breastfeeding women: It is not yet clear whether the medication is secreted through breast milk. It is recommended to suspend breastfeeding during treatment and for at least one week after discontinuing the medication.

(3) Severe liver dysfunction: Child Pugh Class C patients are contraindicated, and mild to moderate liver dysfunction requires dose adjustment and close monitoring of liver enzymes.

2. Forbidden foods

(1) Grapefruits and their products: contain strong CYP3A4 inhibitors, which may significantly increase the blood concentration of Dakatinib and pose a risk of toxicity.

(2) High fat diet: Clinical trials have shown that high-fat meals can increase drug AUC by 40%. It is recommended to take on an empty stomach or after a low-fat diet.

3. Restrictive conditions

(1) Drug interactions: Avoid using CYP3A4 strong inducers (such as rifampicin) or inhibitors (such as ketoconazole) in combination, and adjust the dosage.

(2) Special monitoring requirements: During treatment, regular checks of liver function (ALT/AST), blood potassium, and QT interval on electrocardiogram are required.

(3) Birth restriction: Patients of childbearing age and their partners are required to take dual contraception measures during the medication period and within 3 months after the last dose.