Drugs that can increase T4 measurements include clofibrate, estrogens, methadone, amiodarone, and oral contraceptives.
Drugs that can decrease T4 measurements include anabolic steroids, androgens, antithyroid drugs (for example, propylthiouracil and methimazole), lithium, phenytoin, propranolol, amiodarone, interferon alpha, and interleukin-2.
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others. |
