Everyone has a thyroid. It’s a gland located in neck, under the Adam’s Apple. It’s a part of body, when healthy, you don’t even know is there. But when it’s not healthy, it may swell to the point where you can feel it protruding from the neck. The thyroid, being a gland, is responsible for creating and distributing various hormones throughout the body. One such hormone, thyroxine (or T4), is responsible for functions of the body including managing weight, appetite, metabolism, body temperature, and growth. Usually, when individuals are affected by thyroid issues, the problem is levels of thyroxine.
According to a study conducted in Hong Kong in 1979, Pituitary-thyroid function in male heroin addicts and addicts after abstinence (ex-addicts) was studied and compared with that of healthy euthyroid men. In heroin addicts the increases in circulating total thyroxine and triiodothyronine levels were accompanied by an increase in the thyroid hormone uptake test. These changes may reflect a quantitative increase in thyroxine binding globulin. Reverse triiodothyronine concentrations in heroin addicts were normal. The thyrotrophin-releasing hormone elicited a diminished thyrotrophin response in heroin addicts which was significantly different from that in control subjects and ex-addicts. An elevation of serum prolactin was noted in heroin addicts, while ex-addicts had normal levels. Gradual recovery of pituitary-thyroid function occurred after heroin withdrawal.
In another study in 1980, Pituitary-thyroid function has been studied in heroin addicts. Data have been obtained in 10 male addicts, aged 18-24 years, with histories of addiction to heroin alone lasting from 8 months to 4 years, and control group. In this study the levels of TSH, T4 and T3 were measured. Also, a TRH stimulation test was done. The results revealed no difference between addicts and controls in basal levels of TSH, T4 and T3.
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2265.1979.tb02115.x
https://www.ncbi.nlm.nih.gov/pubmed/8868137
https://www.researchgate.net/publication/23022161_Effects_of_heroin_addiction_on_thyrotrophin_thyroid_hormones_and_prolactin_secretion_in_men
https://www.ncbi.nlm.nih.gov/pubmed/113145