How to treat hyperthyroidism with elevated Glutamic-Oxaloacetic Transaminase (GOT) and Glutamic-Pyruvic Transaminase (GPT) due to Thyrozol (Propylthiouracil)?

From the Guidelines

To treat hyperthyroidism with elevated GOT and GPT due to thiamazole (Thyrozol), I recommend switching to an alternative antithyroid medication such as propylthiouracil (PTU) at a starting dose of 100-150 mg three times daily, as thiamazole-induced liver dysfunction requires discontinuation of the medication, and PTU has a different hepatic metabolism profile 1. The goal of treatment is to maintain FT4 or FTI in the high-normal range using the lowest possible thioamide dosage, and measuring the FT4 or FTI every two to four weeks can be helpful 1. Some key points to consider when treating hyperthyroidism with elevated liver enzymes include:

• Monitoring liver function tests weekly initially, then every 2-4 weeks as enzymes normalize
• Considering adding a beta-blocker such as propranolol 10-40 mg three to four times daily to control hyperthyroid symptoms while the new medication takes effect
• If both thiamazole and PTU cause liver problems, definitive treatment with radioactive iodine or thyroidectomy may be necessary
• Regular monitoring of both thyroid function (TSH, free T4) and liver enzymes is essential throughout treatment to ensure proper management of both conditions It's also important to note that agranulocytosis, a side effect of thioamides, usually presents with sore throat and fever, and if these symptoms develop, a complete blood cell count should be obtained, and the thioamide should be discontinued 1. Additionally, other side effects of thioamides include hepatitis, vasculitis, and thrombocytopenia, and suppression of fetal and neonatal thyroid function can occur with thioamide therapy for Graves' disease, but it is usually transient, and treatment is rarely required 1.

From the FDA Drug Label

Propylthiouracil inhibits the synthesis of thyroid hormones and thus is effective in the treatment of hyperthyroidism. The drug does not inactivate existing thyroxine and triiodothyronine that are stored in the thyroid or circulating in the blood, nor does it interfere with the effectiveness of thyroid hormones given by mouth or by injection. Propylthiouracil inhibits the conversion of thyroxine to triiodothyronine in peripheral tissues and may therefore be an effective treatment for thyroid storm.

To treat hyperthyroidism with elevated GOT and GPT due to thyrozol, propylthiouracil (PO) can be used as it inhibits the synthesis of thyroid hormones.

• The patient should be under close surveillance and report any symptoms of hepatic dysfunction or illness.
• Liver function tests should be monitored periodically during therapy.
• The dose of propylthiouracil should be adjusted based on thyroid function tests and clinical evidence of hyperthyroidism.
• Patients should be counseled regarding the necessity of immediately reporting any evidence of illness or symptoms suggestive of hepatic dysfunction 2.
• Propylthiouracil may be the treatment of choice when an antithyroid drug is indicated during or just prior to the first trimester of pregnancy 2.

From the Research

Treatment Options for Hyperthyroidism

• Hyperthyroidism can be treated with antithyroid medications, radioactive iodine ablation of the thyroid gland, or surgical thyroidectomy 3
• The choice of treatment depends on the underlying diagnosis, the presence of contraindications to a particular treatment modality, the severity of hyperthyroidism, and the patient's preference 3

Elevated Liver Enzymes in Hyperthyroidism

• Abnormal liver blood tests are common in patients with hyperthyroidism, with a prevalence of 55% to 60% 4
• The most common abnormalities are elevated alanine transaminase (ALT) and aspartate transaminase (AST) 4
• Antithyroid drug (ATD) therapy can normalize liver enzyme abnormalities in 83% to 87% of cases 4

Treatment of Hyperthyroidism with Elevated Liver Enzymes

• Methimazole is a common antithyroid medication used to treat hyperthyroidism, and it can also help normalize liver enzyme abnormalities 5, 6
• Radioactive iodine ablation is also an effective treatment option, but it may take longer to achieve euthyroidism compared to methimazole 6
• Long-term methimazole treatment is superior to radioactive iodine treatment in achieving sustained euthyroidism in patients with toxic multinodular goiter 6

Specific Treatment for Thyrozol-Induced Hyperthyroidism

• There is no specific study on the treatment of hyperthyroidism induced by thyrozol, but the general treatment options for hyperthyroidism can be applied 3, 4, 5, 6, 7
• The treatment should be chosen based on the underlying diagnosis, the presence of contraindications, the severity of hyperthyroidism, and the patient's preference 3