Hormonal Methadone

Prolonged therapy with methadone causes increases in serum thyroid hormone-binding globulin, triiodothyronine, and thyroxine, as well as albumin, globulin, and prolactin, and these must be monitored (SEDA-15, 71 SEDA-17, 81). 

There are other physiological effects of methadone for which there is no known mechanism. In women who use methadone, there can be changes seen in their menstrual cycle. It has been hypothesized that these changes are due to methadone s effect on the hormones that regulate menstmation, but this has not yet been proven. 

The outstanding properties of methadone are its analgesic activity, its efficacy by the oral route, its extended duration of action in suppressing withdrawal symptoms in physically dependent individuals, and its tendency to show persistent effects with repeated administration. Miotic and respiratory-depressant effects can be detected for more than 24 hours after a single dose, and on repeated administration, marked sedation is seen in some patients. Effects on cough, bowel motility, biliary tone, and the secretion of pituitary hormones are qualitatively similar to those of morphine. 

The administration of ji agonists increases the concentration of prolactin in plasma, probably by reducing the dopaminergic inhibition of its secretion. The administration of morphine or P-endorphin has little effect on the concentration of growth hormone in plasma. With chronic administration, tolerance develops to the effects of morphine on hypothalamic releasing factors. Patients maintained on methadone reflect this phenomenon in women, menstrual cycles that had been disrupted by intermittent use of heroin return to normal in men, circulating concentrations of LH and testosterone return to the normal range. 

Classes of substances currently banned by the IOC include stimulants (amphetamines, cocaine, caffeine, pseudoephedrine), narcotics (heroin, methadone), anabolic agents (testosterone, nandrolone), diuretics (acetazolamide, spironolactone), and peptide hormones and their mimetics and analogs (erythropoietin, human growth hormone). Alcohol and marijuana at specified levels are also prohibited. For the latter, a level of as little as 15 ng/mL of 11-nor-A°-tetrahydrocannabinol-9-carboxylic acid is a violation of the rules. A complete... 

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