Ambroxol is a phlegm chemotherapeutic drug that is generally safe, but may cause some adverse reactions such as allergic reactions, digestive upset, and other related harm. 1. Allergic reactions: for example, skin rashes and itching may occur, and in severe cases may lead to anaphylaxis. 2. Gastrointestinal discomfort: These include nausea, upset stomach, lack of appetite, and related symptoms such as diarrhea and abdominal pain. 3. Other hazards: for example, in a few cases, it may cause dizziness, headache and other related manifestations. Ambroxol needs to be concerned about its adverse reactions during use, and once they occur, the drug should be stopped promptly for treatment. In addition, it is contraindicated for those who have a previous history of allergy to the product. Ambroxol needs to be used under the guidance of a doctor, unauthorized use of the drug is not recommended.