The professional name of headache powder is Acetaminophen, which can relieve fever as well as headache. Long-term overdose may cause side effects such as drug addiction, gastrointestinal reactions, skin allergic reactions, and liver and kidney function damage. 1, drug addiction: headache powder is a compound preparation, containing a certain amount of aspirin, acetaminophen and a small amount of caffeine. Caffeine is a kind of central nervous stimulant, if taken for a long time or in excess, it may form dependence and lead to drug addiction. 2, gastrointestinal reactions: headache powder contains a certain amount of aspirin, may cause irritation to the gastric mucosa, some patients after taking nausea, vomiting, discomfort or pain in the lower abdomen, etc. Long-term use of the drug may easily lead to damage to the gastric mucosa, causing gastric bleeding or gastric ulcers. 3, skin allergic reactions: atopic constitution people exposed to aspirin and acetaminophen in headache powder will have skin allergic reactions such as rash, urticaria and skin itching. 4. Liver and kidney function damage: If a large amount or long-term headache powder is taken, an excessive amount of acetaminophen will be ingested, thus causing damage to the liver. After taking the drug for several months, some patients may experience discomfort or tenderness in the right upper abdomen. At this time, they should stop taking the drug in time and take amino acid rehydration, oral prednisone and other drugs to relieve discomfort under the guidance of doctors.