Pregnant women with hyperthyroidism can be treated with propylthiouracil tablets, but they should be careful about the dosage and duration of use. Propylthiouracil can prolong the prothrombin time and increase AST , ALT. Overdose can lead to hypothyroidism, which may manifest as weakness, easy fatigue, fear of cold, lack of interest in everyday things, loss of concentration and weight gain, and also symptoms such as chest pain, impaired blood supply, shortness of breath, rheumatic pain, and numbness in the hands and feet. It is important to closely monitor the changes in the white blood cell count during administration and to discontinue the drug if it is too low or if there is a tendency of continuous decline. Because it has no teratogenic or fetal growth and development side effects, it can be used by pregnant women with hyperthyroidism, but it is better not to use it during lactation.