We recently met a patient who had mild jaundice and an increase of alanine aminotransferase (ALT, also called glutamate aminotransferase, or PT, as we say in Shanghai) more than 8 times the normal value after taking eugenol and herbal decoction for thyroid cyst. The jaundice subsided and the ALT basically decreased to normal after more than a month, but during the continuation of liver care treatment, it was found that the ALT did not continue to improve but gradually increased to 156 again, and despite two months of treatment by switching to different liver care drugs (diammonium glycyrrhizate capsules, silymarin and pentaerythritol capsules, etc.), the effect was still poor. This patient friend had a history of hepatitis E 8 years ago, which was cured by hospitalization, and her liver function and hepatobiliary and splenic ultrasound were normal at annual follow-up. She came to our Gastroenterology Clinic at the Shanghai Public Health Clinical Center for advice when she was ready to accept some recommendations to increase the dosage of her liver protection medication. Based on the fact that this patient’s friend was positive for Ig G antibodies to hepatitis E but did not clinically support the diagnosis of hepatitis E and laboratory serology did not support hepatitis A, B and C, this friend developed liver function abnormalities after taking eugenol and certain Chinese herbs that have liver-damaging side effects, consistent with the diagnosis of drug-related liver injury. His liver function changes showed an inverted parabolic phenomenon of high ALT before liver protective drug therapy, basically normal after a period of treatment, and elevated again with continued consolidation therapy. We carefully analyzed this patient’s condition and medication process, and we believe that at this time, the hepatoprotective drugs have lost their therapeutic effect on the liver for this patient, and there is no need to continue using these drugs. This inverted parabolic phenomenon of liver protector treatment indicates that this patient’s friend has a hypersensitivity reaction in the body based on the pathology of liver injury by drugs, and any drug, even if it is a liver protector, will cause and aggravate liver function damage in this state, while some liver protectors will also cause damage to the liver by accumulating in the body for a long time. The liver is an important metabolic organ in the human body, normally involved in the body’s protein, fat, glucose metabolism, but at the same time the liver is the body’s main detoxification organ, taking any drug, its pharmacological and toxic reactions are mainly through the liver metabolism. Therefore, the application of any drug will increase the burden on the liver, and even cause liver damage, even if it is liver-protective drugs. This friend did not apply any other medication except liver-protective drugs, and the ALT did not recover, which could only be the adverse reaction of liver-protective drugs, there is no other explanation. In addition, this patient friend had negative autoimmune index tests several times and no history of heavy alcohol consumption, etc., which could exclude other diseases that could cause ALT increase. Based on the above analysis, we recommended that this patient stop all medications he was taking and follow up. At first, although he thought our explanation was reasonable, he was still skeptical and did not understand: He had only heard of increasing the amount of medication for a disease that was not well treated, but could he be cured by stopping the medication? Every day, this patient friend calls us to ask if she should add some of this or that medicine. We patiently advised her not to think about anything, to eat and sleep at home as she did when she was hospitalized, not to do strenuous physical activities, and to wait quietly for two weeks, and if the liver function did not improve again, it was not too late to increase the medication. Two weeks later, a miracle happened. When we walked into the clinic at eight o’clock in the morning, we saw this patient friend already sitting in the waiting room, and when he saw us coming, he stood up and waved his labs high, “PT is down!” After another two weeks of silence, the “PT” continued to drop significantly, and one and a half months later, the liver function was normal. The patient said with emotion, “Liver medicine should be taken wisely too!