Also called male breast enlargement, gyno · Reviewed
Definition:Gynecomastia is the growth of breast gland tissue in males. The NCI dictionary says it can come from a hormone imbalance, from conditions that affect hormones such as tumors or kidney, liver or thyroid disease, or from certain drugs, and that it can occur at any age.
What the labels say
Testosterone: the AndroGel label has a warning that breast enlargement may develop and persist. It appears on the other testosterone labels on this site too.
Spironolactone: Aldactone names gynecomastia as its most common side effect. About 9% of men on a mean 26 mg a day developed it in the RALES heart failure trial.
hCG: the Pregnyl label says gynecomastia can occur in men.
On testosterone, some of the hormone is turned into estradiol by the aromatase enzyme, which is why breast changes on TRT often lead to an estradiol test.
What it feels like
It usually starts as a firm or tender area under the nipple, on one side or both. Fat in the chest without gland tissue is not gynecomastia, and a clinician can tell them apart on exam. The AndroGel wording, that it may develop and persist, is a reminder that it does not always go away on its own once it starts.
Why it matters for your log
Breast tenderness tends to show up weeks after a dose change. Keeping the date of the first change next to dose history and estradiol results makes the prescriber's question of "since when" easy to answer.
General education drawn from labels and published studies, not personal medical advice. Your prescriber, pharmacist and the label that came with your product are the final word.
Yes. The AndroGel label warns that breast enlargement may develop and persist, and the other testosterone labels carry the same warning.
Which medicines are known to cause gynecomastia?+
Among the labels on this site, it is listed for testosterone products, spironolactone (about 9% of men in the RALES trial) and hCG. The NCI dictionary notes that certain drugs are one of several causes.