Although Zhang Lao Han was 79 years old, he was in good health and had no major physical illnesses. two days before the Spring Festival 2011, he had cold symptoms such as nasal congestion, dizziness and runny nose. his son went to a pharmacy in a nearby town and bought a box of Neocontek (each capsule contains 90mg of pseudoephedrine hydrochloride and 4mg of chlorpheniramine maleate) and gave him 2 capsules/time, taking a total of 4 capsules twice that day. At about 11:00 p.m., the patient started to become hyperactive, unable to sleep, talking to himself and behaving strangely, claiming that robbers were coming, tying some of his things into parcels and carrying them behind his back, while running and telling his family to run away. The family did not know what to do when they saw the situation, and when they found out that the author was home for the Chinese New Year, they came to my house to look for me. At that time, after asking the reason for the incident, I did a physical examination with my bare hands and saw only mild congestion in the pharynx, no significant abnormalities in pulse and breathing, and no significant abnormalities in the abdomen. The mental examination found that Zhang Lao Han was not clearly conscious, his time orientation was not normal, his person and place orientation were fine, he had difficulty communicating with them, he was inattentive, his emotions were not coordinated, he cried and laughed at times, he had hallucinations, he said he saw robbers and heard them say they were going to rob his family’s belongings, and he lost his self-awareness. The old man fell asleep quickly and slept through the night, waking up at 10:00 the next day with his speech and behavior back to normal, unable to fully recall what happened last night. Zhang’s state at that time should be diagnosed as neocontec overdose induced mental disorder (delirium state). Neocontec is a commonly used over-the-counter drug for the treatment of cold symptoms in adults. Its main component, pseudoephedrine hydrochloride, is an adrenaloid, but has a stronger excitatory effect on the central nervous system than adrenaline. The function and reserve capacity of various organs of the elderly, especially the liver and kidney function, decreases in varying degrees with age, so that the elderly do not adapt to various stressful situations as quickly as adults. Therefore, the absorption, distribution, metabolism and excretion of drugs in the body will be affected. The slightest carelessness in the use of drugs may cause toxic side effects. Therefore, when using drugs for the elderly, the following points should be noted: 1, the use of drugs need to have a doctor’s exact diagnosis, a clear diagnosis is the basis of treatment, sickness to the regular hospital. Patients with chronic diseases should not use medication at will. 2, the elderly should be under the guidance of a doctor, the use of drugs, dosage to effectively follow medical advice. Do not increase the dosage at will simply because you hope for a fast cure. 3, try to avoid the use of drugs, drugs are only one aspect of the treatment of disease, many discomfort of the elderly, such as constipation, insomnia, etc., can be adjusted through food. When medication is necessary due to illness, it should be used as little as possible, especially for the elderly who do not have their own medication and need the assistance of others to use medication, should be extra careful. 4, pay attention to the dosage of drugs, in general, less than 80 years old elderly, according to the physical condition of its dosage of 2/3-4/5 of the adult dosage, 80 years old or more than 80 years old, the dosage of drugs for the adult amount of 1/2. 5, pay attention to the observation of drug reactions, once the occurrence of adverse drug reactions, to promptly stop the drug, if necessary, consult a doctor, replace the role of the same or similar, less toxic side effects of drugs.