Chaihu injection contraindications suggested that the drug is contraindicated to mix with other drugs, and both drugs can produce allergic reactions, so Chaihu injection and penicillin can not be mixed injection. Chaihu Injection is a proprietary Chinese medicine preparation with the effect of clearing away heat and relieving the surface, mainly used for the treatment of fever caused by malaria, influenza, etc. The dosing instructions indicate that the drug should be used in combination with other drugs. Its instructions for use show that the drug should be used alone, mixing and matching is strictly prohibited, and mixing and matching with other drugs is contraindicated. The adverse reactions of both Chaihu injection and penicillin are allergic reactions, which are lethal in severe cases, so Chaihu injection and penicillin can not be mixed and injected. The specific use of Chaihu Injection and Penicillin should be standardized under the guidance of professional doctors. Chaihu injection and penicillin can cause allergic reactions, so the medication should be observed at any time.