Eating metformin thirst, there may be drug side effects, or blood sugar is not controlled. 1. Drug side effects: Metformin can lead to abnormal taste, a part of the population feel a metallic taste in the mouth, bitter taste, affecting appetite, metallic taste, etc. can easily be mistaken for thirst, need to drink water to eliminate the odor. There is also a possibility that due to loss of appetite, the water obtained from food is correspondingly reduced, feeling thirsty, need to drink more water. 2. Diabetes: One of the symptoms of diabetes itself is excessive drinking, accompanied by thirst, so it is also important to consider the case that blood sugar is not under control, and you need to actively seek medical attention, check your blood sugar, etc., and adjust your medication according to the results. There are many causes of thirst, it is recommended to actively seek medical attention to find the cause, under the guidance of the doctor’s treatment.