Men and boys who take the psychiatric drug risperidone may be at risk for developing gynecomastia. While this condition may seem alarming at first, it’s usually not hard to treat. Most cases can be resolved by a simple change in medication.

Gynecomastia refers to the abnormal development of breast tissue in men. It’s not just an increase in fat around the breast area – although drugs like risperidone can also bring on weight gain that accentuates gynecomastia. True gynecomastia is an overdevelopment of existing breast tissue, which is naturally present in men’s bodies but usually does not develop the way it does in women.

Sometimes gynecomastia happens naturally. Newborn babies, adolescent boys, and men middle-aged and older sometimes go through short periods of gynecomastia due to the hormonal changes going on at those ages.

The condition can also result from the use of several different types of medications. In particular, certain psychiatric medications like antidepressants and anti-anxiety drugs have been associated with the condition. One such medication is risperidone, a medication used to treat behavioral issues associated with various psychiatric conditions.

Risperidone is also sold under the brand name Risperdal. Today it’s approved by the FDA to treat symptoms of schizophrenia, manic and mixed episodes associated with bipolar disorder, and behavioral problems like aggression and self-injury in young people with autism.

How Risperidone Can Stimulate Breast Development

Scientists believe that part of risperidone’s normal mechanism of action may cause gynecomastia by altering a person’s normal balance of hormones. Risperidone works in part by blocking the action of the neurotransmitter dopamine. That reduction in dopamine activity causes the pituitary gland to release more of the hormone prolactin.

Prolactin is typically associated with normal breast development and production of breast milk in women. Taking risperidone can cause similarly high levels of prolactin in men. Researchers believe this increase in prolactin may be how some risperidone patients end up developing gynecomastia.

Gynecomastia that’s caused by a medication usually goes away once the patient stops taking that medication. Rarer cases may fail to resolve even after the medication is stopped. In that case, the patient may need to resort to gynecomastia surgery to remove the excess breast tissue. Liposuction may also help restore the normal shape of the chest by removing any excess fat.

Like other types of surgery, gynecomastia surgery comes with the risk of certain complications like scarring, infection, or nerve damage.

Litigation Over Risperidone

Risperidone and its association with gynecomastia has been the subject of hundreds of lawsuits against Risperdal’s manufacturer Janssen Pharmaceuticals and its parent company Johnson & Johnson.

Generally, plaintiffs in these lawsuits developed gynecomastia after they were prescribed Risperdal as young men or boys. They argue that Janssen failed to warn them and their doctors about the risk of male breast growth associated with the drug.

Many of these plaintiffs take issue with the way Janssen allegedly promoted Risperdal for use in young patients at a time when the FDA had approved the drug only for use in adults. These allegations were the subject of several regulatory prosecutions brought by the federal government and several states. Janssen and J&J have already settled several of these actions, but not without having to pay hundreds of millions of dollars in penalties.