Thyroid is a tiny gland that is located at the base of neck, right below Adam’s apple. The gland contains hormones that regulate multiple functions in body, including metabolism, heart rate, body temperature, and so on. If these thyroid hormones are secreted less or more than normal, they can cause serious problems in the body. Thyroid gland function is examined by various tests. In most cases, levels of TSH, T4, and T3 hormones are measured. If the level of each of these hormones is lower or higher than normal, it indicates a thyroid dysfunction (hypothyroidism or hyperthyroidism).
Increasing rate of narcotics consumption is one of the major challenges in most countries. Among narcotics, opium and heroin have high rate of consumption around the world. The effects of long-term consumption of opium on endocrine system have not been investigated so much and most related studies have focused on the effects of heroine which is the most major consumed narcotic in western countries. A number of abnormalities has been identified among drug addicted users especially heroin addicts. However, there are a few studies to assess the opium effects on thyroid hormones. To study the effect of drugs on thyroid hormones, levels of TSH, T3, and T4 hormones have been studied in several studies.
In one of the studies, 50 male addicts, aged 20–50 years, with history of addiction to opium lasting more than two years, and 50 male non-addicts as control group were randomly selected. 10 cc blood sample and 50 cc urine sample was taken for measurements of thyroid hormones (TSH, total T4, T3, T4, and T3RU). The analysis revealed that there was not a significant association between opium and serum levels of T4 and TSH, but compared with control group, a slight increase in total T3 and a decrease in T3RU were observed among addicts. The findings of the present study demonstrated that opium can influence on thyroid function by increasing total T3 and decreasing T3RU and free T4 levels.
Pituitary and thyroid function in male heroin addicts and addicts after abstinence (exaddicts) was studied and compared with that of healthy euthyroid men. In heroin addicts the increases in circulating total thyroxin (T4) and triiodothyronine (T3) levels were accompanied by an increase in the thyroid hormone uptake test. These changes may reflect a quantitative increase in thyroxin binding globulin.