Compound menthol nasal drops are vasoconstrictors and are not suitable for prolonged application, which can lead to the following hazards. First, drug-related rhinitis. Long-term use of compound menthol nasal drops will lead to long-term vasoconstriction in the nasal cavity, causing hyperplastic changes in the local nasal mucosa tissue, which in turn will lead to the occurrence of drug rhinitis. Second, prolonged use of this product can lead to dizziness, headaches and other uncomfortable symptoms. Because of poor local blood circulation caused by prolonged contraction of the nasal mucosa tissue, the cerebral blood vessels may also suffer from symptoms of insufficient blood supply.