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Women aren’t the only ones getting boob jobs.
While gynecomastia, or enlarged male breast tissue, often resolves on its own, a growing number of men are turning to plastic surgery to achieve a flatter, more contoured chest.
The condition most commonly appears during natural hormonal shifts like puberty, but other triggers can play a role as well. From heart drugs to hair-loss treatments, here’s a look at 10 common medications linked to an increased risk of gynecomastia.
Spironolactone
A diuretic that helps the body remove excess fluid and sodium, spironolactone is commonly sold under the brand name Aldactone and is used to treat high blood pressure, heart failure and swelling linked to the heart, kidneys or liver.
It can trigger gynecomastia by disrupting hormone balance, lowering the effects of testosterone, the main male sex hormone, and allowing estrogen, a hormone linked to female breast development, to have more influence in the body.
Finasteride
This drug is commonly prescribed under brand names like Propecia for hair loss and Proscar for enlarged prostates, a common issue in aging men.
It works by blocking the conversion of testosterone into dihydrotestosterone, or DHT, a hormone strongly linked to prostate growth and hair loss.
By lowering DHT, it can disrupt normal male hormone activity and, in some men, trigger chest enlargement linked to gynecomastia.
Anabolic Steroids
Best known for their misuse by bodybuilders, athletes and others chasing muscle gains, these synthetic versions of testosterone also have legitimate medical uses, including low testosterone, delayed puberty, and muscle wasting.
Unlike drugs that reduce male hormones, anabolic steroids can flood the body with high levels of testosterone. Some of it can then be converted into estrogen, which may stimulate male breast development.
Antipsychotics
These medications are used to treat conditions like schizophrenia, bipolar disorder, Tourette’s syndrome, and severe behavioral problems in children that don’t respond to other treatments.
One common drug, haloperidol, sold under the brand name Haldol, works by blocking dopamine receptors in the brain, helping rebalance a chemical that plays a key role in mood, behavior and thinking.
But in some cases, that change can raise levels of prolactin, a hormone involved in breast development. When prolactin increases, it can also lower testosterone and disrupt hormone balance, which may lead to changes in chest tissue in men.
Risperidone, an antipsychotic sold under the brand name Risperdal, can have a similar effect.
Nonsteroidal Antiandrogens
This class of medications is commonly used in prostate cancer treatment and includes drugs like bicalutamide, sold under the brand name Casodex, and flutamide, sold under the brand name Eulexin.
They work by blocking testosterone and DHT from binding to receptors in the body, preventing them from stimulating cancer cells.
Both drugs can cause gynecomastia by disrupting hormone balance, allowing estrogen to become more dominant and stimulate breast tissue growth.
Diazepam
Sold under the brand name Valium, this drug calms the nervous system and is used to treat anxiety, muscle spasms, seizures and symptoms of alcohol withdrawal.
It works by boosting the effects of GABA, a natural brain chemical that has a calming effect.
In rare cases, it may also interfere with hormone regulation in a way that allows estrogen’s effects to become more noticeable, which can contribute to gynecomastia.
Cimetidine
Commonly used to treat heartburn, acid reflux and GERD, this medication is often sold under the brand name Tagamet and works by reducing the amount of acid the stomach produces.
It can also have weak anti-androgen effects, meaning it may reduce testosterone activity in the body.
That shift can allow estrogen to have a stronger influence and potentially lead to gynecomastia.
Ketoconazole
Ketoconazole, typically sold under the brand name Nizoral, is an antifungal used to treat skin infections like athlete’s foot, jock itch, ringworm and seborrheic dermatitis.
However, it can also interfere with the body’s production of testosterone.
Lower testosterone levels can shift the hormone balance toward estrogen, which may result in male breast changes.
Metronidazole
Metronidazole, sold under the brand name Flagyl, is an antibiotic and antiparasitic used to treat infections in the stomach, skin, reproductive system and other parts of the body.
It works by entering bacteria and parasites and damaging their DNA, preventing them from multiplying.
In rare cases, it has been linked to gynecomastia, although the exact reason is not fully understood.
