Main Research Findings

Methimazole, a common drug for treating hyperthyroidism, has been found to have various side effects. Some studies suggest that combining methimazole with berberine can improve treatment outcomes and potentially reduce side effects by modulating the intestinal microbiome. 9 Other research focuses on desensitization strategies to methimazole for patients experiencing skin reactions, allowing continued treatment with methimazole. 15 Furthermore, studies have explored the impact of methimazole on blood sugar control in patients with Graves' disease and type 2 diabetes mellitus, finding that methimazole can cause hypoglycemia. 2

Reasons for Side Effects

Methimazole's side effects stem from its mechanism of action, which involves inhibiting the production of thyroid hormone by blocking the enzyme peroxidase. This inhibition can affect not only thyroid tissue but also other tissues, potentially leading to a range of side effects. 15 , 2

Common Side Effects

Skin Reactions

Common side effects associated with methimazole include skin reactions like rash and itching. 15

Liver Damage

Methimazole has been linked to liver damage, which can be indicated by elevated liver enzyme levels. 25 , 22

Blood Cell Reduction

Methimazole can lead to a reduction in blood cells, particularly white blood cells, which can increase the risk of infections. 4 ,

Hypoglycemia

Methimazole can cause hypoglycemia, especially in patients with type 2 diabetes mellitus. This is likely due to methimazole's effect on insulin. 2

Birth Defects

Methimazole use during pregnancy, particularly in the first trimester, has been associated with an increased risk of birth defects. 24 , 18 , 22

Others

Other side effects reported with methimazole include gastrointestinal disorders, taste disturbances, hair loss, fever, and joint pain. 17

Countermeasures for Side Effects

Skin Reactions

Skin reactions can often be managed by stopping or reducing the dosage of methimazole. Additionally, topical treatments like steroid creams may help alleviate symptoms. 15

Liver Damage

If liver damage occurs, methimazole should be discontinued, and the patient should be closely monitored until liver function recovers. In severe cases, liver transplantation may be necessary. 25 , 22

Blood Cell Reduction

Blood cell reduction requires immediate discontinuation of methimazole. Treatments like blood transfusions may be necessary. In severe cases, bone marrow transplantation might be considered. 4 ,

Hypoglycemia

Careful monitoring of blood sugar levels is essential for patients taking methimazole, especially those with type 2 diabetes. Adjusting diabetes medication may be required. 2

Birth Defects

Pregnant women requiring methimazole treatment should discuss the risks and benefits with their doctor. Propylthiouracil (PTU) is often preferred in the first trimester, with methimazole considered safer in later stages of pregnancy. 24 , 18 , 22

Others

Managing other side effects typically involves discontinuing or reducing the dosage of methimazole and implementing appropriate treatments based on the specific symptom. 17

Comparison between Studies

Common Points

Multiple studies highlight the potential for methimazole to cause a range of side effects, including skin reactions, liver damage, blood cell reduction, and hypoglycemia. The research emphasizes the importance of being aware of these potential risks and discussing them with a healthcare professional.

Differences

The specific frequency and severity of side effects associated with methimazole can vary depending on the study. Some studies emphasize liver damage as a more prominent risk, while others highlight blood cell reduction. This suggests that individual factors and the specific context may influence the type and likelihood of side effects.

Points to Note Regarding Application in Real Life

Methimazole remains a valuable treatment for hyperthyroidism, but it is crucial to understand the potential side effects. Always discuss the risks and benefits with your doctor before starting methimazole. Closely monitor your health while taking the medication and seek medical attention promptly if you experience any unusual symptoms or changes in your condition.

Limitations of Current Research

Research on methimazole's side effects is still ongoing. The long-term effects, in particular, are not fully understood. Further research is needed to provide more comprehensive insights into the risks associated with methimazole.

Directions for Future Research

Continued research on the side effects of methimazole is essential, with a focus on long-term effects and strategies to mitigate or prevent side effects. The development of alternative treatments with fewer side effects would also be a significant advancement.

Conclusion

Methimazole is a helpful medication for hyperthyroidism, but being aware of potential side effects is vital. Consult with your doctor before taking methimazole to discuss the risks and benefits. Be attentive to your health during treatment and seek medical guidance promptly if any concerns arise.