The effect of combination therapy with propylthiouracil and cholestyramine in the treatment of Graves' hyperthyroidism.
OBJECTIVE
The study aims to evaluate the efficacy of combination therapy with propylthiouracil (PTU) and cholestyramine in the treatment of Graves' hyperthyroidism.


BACKGROUND
Thyroxine (T4) is metabolized mainly in the liver by conjugation to glucuronides and sulphates that enter the enterohepatic circulation. Thyrotoxic patients have an abnormal increase in thyroid hormone in their enterohepatic circulation. Previous studies on combination therapy with methimazole and cholestyramine for Graves' hyperthyroidism have shown it to be an effective adjunctive treatment. In this study, we examined the efficacy of combination therapy with PTU and cholestyramine in the treatment of Graves' hyperthyroidism.


METHODS
Thirty patients with newly diagnosed Graves' hyperthyroidism were randomly divided into two groups: group I (n = 15) received PTU 100 mg twice a day, propranolol 40 mg twice a day and cholestyramine 4 g twice a day for 4 weeks; group II (n = 15) received PTU 100 mg twice a day and propranolol 40 mg twice a day for 4 weeks. The therapeutic efficacy was determined by serum total triiodothyronine (TT3), free thyroxine (FT4) and TRAb levels at baseline, and at the end of 2 and 4 weeks during the study period.


RESULTS
There was no significant difference in baseline thyroid function parameters. At the end of 2 and 4 weeks of the study period, serum TT3 and FT4 levels of group I were significantly lower than those of group II. No significant differences in the TRAb level were found between the two groups.


CONCLUSIONS
Cholestyramine contributed to a more rapid and complete decline in thyroid hormone levels in patients with Graves' hyperthyroidism. It was thus proved to be an effective and well-tolerated adjunctive therapy.
Tsai
Wen-Chin
WC
Division of Endocrinology and Metabolism, Department of Internal Medicine, Buddhist Tzu-Chi General Hospital, Tzu-Chi University, Hualien, Taiwan, China.
Pei
Dee
D
Wang
Tso-Fu
TF
Wu
Du-An
DA
Li
Jer-Chuan
JC
Wei
Cheng Lian
CL
Lee
Chien-Hsing
CH
Chen
Sheng-Pyng
SP
Kuo
Shi-Wen
SW
D000293:Adolescent; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000328:Adult; D013956:Antithyroid Agents / Q000627:therapeutic use*; D001323:Autoantibodies / Q000097:blood; D002792:Cholestyramine Resin / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D006111:Graves Disease / Q000097:blood / Q000188:drug therapy*; D006801:Humans; D007475:Ion Exchange Resins / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011433:Propranolol / Q000627:therapeutic use; D011441:Propylthiouracil / Q000627:therapeutic use*; D011988:Receptors, Thyroid Hormone / Q000276:immunology; D013960:Thyroid Function Tests; D013974:Thyroxine / Q000097:blood; D013997:Time Factors; D016896:Treatment Outcome; D014284:Triiodothyronine / Q000097:blood
D000319:Adrenergic beta-Antagonists; D013956:Antithyroid Agents; D001323:Autoantibodies; D007475:Ion Exchange Resins; D011988:Receptors, Thyroid Hormone; D014284:Triiodothyronine; D002792:Cholestyramine Resin; D011441:Propylthiouracil; D011433:Propranolol; D013974:Thyroxine