A Rispderdal gynecomastia lawsuit was filed by a Baton Rouge, La., woman alleging the anti-psychotic medication Risperdal caused her now 13-year-old son to develop a condition known as gynecomastia, the growth of abnormally large breasts in males.

Gynecomastia, commonly referred to as “man boobs,” is characterized by the excess growth of breast tissue, not excess fat tissue. The Risperdal lawsuit is one of nearly 1,000 pending cases.

Plaintiffs accuse global pharmaceutical giant Johnson & Johnson and Janssen Pharmaceuticals of concealing Risperdal’s effects, improperly marketing the drug for off-label uses and of the drug causing serious side effects, including gynecomastia in boys and young men.

The boy’s mother is seeking compensation in federal court for medical expenses, pain and suffering, mental anxiety and anguish, loss of wages and earnings, loss of future earning capacity and loss of enjoyment of life.

Her Risperdal lawsuit is one of hundreds filed on behalf of children who took the medication for treatment of bi-polar disorder, autism, irritability, aggression or other behavior disorders.

According to the Mayo Clinic, gynecomastia is swelling of the breast tissue in boys or men, caused by an imbalance of the hormones estrogen and testosterone. It is triggered by a decrease in the amount of the hormone testosterone compared with estrogen. Gynecomastia can affect one or both breasts, sometimes unevenly.

Swollen breast gland tissue, pain, breast tenderness and nipple discharge in one or both breasts are common signs of the condition.

A 21-year-old man reached a confidential settlement with Johnson & Johnson in 2012 after filing a lawsuit blaming Risperdal for causing him to grow abnormally large breasts, resulting in “severe psychological trauma.”

The plaintiff had a mastectomy to remove the breasts. Johnson & Johnson also later settled cases brought on behalf of at least five other boys who experienced breast development.

The medical journal Plastic and Reconstructive Surgery has reported that research shows that even mild breast growth can have a serious, negative psychological impact on boys.

Male breast growth is gradual, often beginning with nipple tenderness. The condition can affect one or both breasts. In some cases of gynecomastia, males produce breast milk.

In 2013, the Justice Department announced that Johnson & Johnson would pay more than $2.2 billion to resolve criminal and civil liability arising from allegations related to Risperdal and Invega (used to treat schizophrenia) including promotion for uses not approved as safe and effective by the U.S. Food and Drug Administration and payment of kickbacks to doctors and to the nation’s largest long-term care pharmacy provider.

It represents one of the largest health care fraud settlements in U.S. history, including criminal fines and forfeiture totaling $485 million and civil settlements with the federal government and states totaling $1.72 billion, according to the Department of Justice.