All individuals, whether male or female, possess both female hormones (estrogens) and male hormones (androgens). During puberty, levels of these hormones may fluctuate and rise at different levels, resulting in a temporary state in which estrogen concentration is relatively high. Studies regarding the prevalence of gynecomastia in normal adolescents have yielded widely varying results, with prevalence estimates as low as 4% and as high as 69% of adolescent boys. These differences probably result from variations in what is perceived to be normal and the different ages of boys examined in the studies.
In case of suspected drug-induced gynecomastia, it would be opportune considering a therapy discontinuation. In some cases, it could be helpful reducing the doses or substituting the suspected drug with another one belonging to the same class, but with a weaker association to gynecomastia. 3
Mammography scan allows distinguishing with certainty between gynecomastia and pseudogynecomastia. On the other hand, laboratory tests are necessary for identifying other possible causes, checking the renal, hepatic and thyroid functions and the free-circulating hormones levels. 2
Iatrogenic gynecomastia is generally reversible within 6 months or one year since its onset. If drug discontinuation is not enough or not possible (for example with anti-androgens), a therapy based on tamoxifene (20 mg daily) might be taken into consideration. In fact, despite not being approved for this indication, literature data suggest a response rate of 50-80% of cases, with detectable improvements from the first month of treatment. 3 In the rare eventuality of both drug dechallenge and tamoxifene therapy being unsuccessful, it is possible to resort to surgery or radiotherapy, according to the patient’s needs.
For boys with severe gynecomastia that is causing substantial tenderness or embarrassment, a short course of a drug called tamoxifen (sample brand name: Nolvadex) or raloxifene (brand name: Evista) may be recommended. These drugs block the effects of estrogen in the body and can reduce the size of the breasts somewhat. However, neither of these drugs is approved in the United States for the treatment of gynecomastia. Drugs may be prescribed without US Food and Drug Administration (FDA) approval, although the risks and benefits have not been studied completely.