Ambroxol and carbocysteine which is safer can not be compared, the two adverse reactions are similar, contraindications are different, should be used in accordance with medical advice. Ambroxol is well tolerated, rarely seen mild gastrointestinal discomfort (such as vomiting, nausea, dyspepsia, diarrhea), rash, rare angioneurotic edema, dizziness, headache and other adverse reactions. It is contraindicated in cases of hypersensitivity to Ambroxol. The product should not be used during the 3rd month of pregnancy. Carbocisteine may be seen as adverse reactions such as stomach upset, nausea, diarrhea, mild headache, and rash. Carbocisteine is contraindicated in active peptic ulcers and in those who are allergic to the product. The drug is used with caution in pregnant and lactating women. Both Ambroxol and Carbocisteine can be used for coughing up sputum with difficulty and thick sputum caused by respiratory diseases. They are contraindicated for different groups of people and have similar adverse reactions, so their safety cannot be compared, and they should be used rationally under the guidance of a doctor and according to individual circumstances.