Overnight tea does not have the efficacy and effectiveness of drugs, on the contrary, there may be a loss of nutrients as well as an excessive number of flora, which can lead to health risks. Overnight tea is tea that has been placed overnight. Tea has more tea polyphenols, theaflavin and other nutrients, long-term exposure to air, will be further oxidation, losing the original nutritional value, while leading to deepening color. As tea contains proteins, carbohydrates and other nutrients, when left for a long time, these nutrients will become a good medium for microorganisms, leading to a large number of bacteria, fungi and other microorganisms to multiply, thus increasing the risk of food poisoning, resulting in nausea, vomiting, abdominal pain, diarrhea and other adverse symptoms. In summary, it is not recommended to drink overnight tea, and overnight tea is even less likely to talk about the efficacy and effectiveness of any drug.