Side effects such as diarrhea, stomatitis, interstitial lung disease, keratitis, and onychomycosis may occur with the use of afatinib maleate tablets. Afatinib Maleate Tablet can inhibit tumor growth and is used in the treatment of locally advanced or metastatic non-small cell lung cancer, locally advanced or metastatic squamous histological type of non-small cell lung cancer and other cancers. The use may lead to adverse reactions inflammatory reactions in the organism, including diarrhea, hepatotoxicity, interstitial lung disease, acne-like dermatitis, onychomycosis, cystitis, conjunctivitis such as onychomycosis, stomatitis, and so on. When patients experience uncomfortable symptoms, it is recommended to go to the hospital in a timely manner, strictly under the guidance of a physician to use medication, can not be used privately, adjust the dose of medication or stop the medication, suspected of drug overdose, stop the medication in a timely manner to seek medical attention. The drug is contraindicated in patients who are allergic to afatinib or any excipients, and if it is necessary to use it simultaneously with other drugs, you can consult your physician in advance.