The Food and Drug Administration released a safety announcement yesterday warning that methylphenidate products, one type of stimulant drug used to treat attention deficit hyperactivity disorder (ADHD), may in rare instances cause priapism: a persistent and usually painful erection lasting more than four hours and occurring without sexual stimulation.

Methylphenidate can be found in treatments such as Ritalin, Concerta and Daytrana.

The FDA has updated drug labels and patient Medication Guides to include information about priapism.

Patients who take methylphenidate and develop erections lasting longer than four hours should seek immediate medical treatment to prevent long-term problems with the penis. If not treated right away, priapism can lead to permanent damage to the penis.

According to the FDA review, the median age of patients who experienced priapism was twelve and a half.

Source

Thanks to Bosco.