Chlorpheniramine maleate is an anti-allergic over-the-counter drug, mainly used for urticaria, eczema, allergic rhinitis, drug and food allergies and other diseases, but there are certain hazards, such as affecting safe driving, local metabolic reactions and even systemic diseases. 1, affect the safe driving: because chlorpheniramine maleate will produce inhibitory effects on the central nervous system, dizziness and drowsiness will occur after the drug. Reactions, if taken before driving this substance may affect the driving process, prone to traffic hazards; 2, local metabolic reactions: after taking chlorpheniramine maleate, a small number of patients will appear erythema with itching in the trunk, chest and other parts of the body, may also occur runny nose, nasal congestion and fever and other local metabolic reactions; 3, systemic diseases: chlorpheniramine maleate will burden the liver, causing liver and kidney function It may also aggravate bladder obstruction and cause difficulty in urination and painful urination, or induce gastrointestinal diseases, nausea and vomiting, epigastric discomfort, abdominal pain, etc. Chlorpheniramine maleate should be used correctly according to the doctor’s prescription, do not increase or decrease the dosage without authorization, and try not to drive a vehicle for a long time while taking the drug.