A Sioux City man is going to prison for a second time for selling unapproved versions of drugs used to treat erectile dysfunction.

Sixty-one-year-old David Kempema was sentenced to 18 months in prison after he pleaded guilty to selling misbranded drugs with the intent to defraud. Information from his plea agreement showed Kempema ordered pills from India or Germany that contained the same active ingredients as Viagra and Cialis.

He placed ads in men’s restrooms in businesses along Interstate 29 advertising the pills as “dietary supplements” called “Supermale” and “All Natural Male.” Kempema admitted that he knew the drugs were not FDA-approved. He had reached another plea agreement for doing about the same thing back in 2011 and was sentenced back then to 60 days in jail.

Prosecutors say drugs from overseas may contain unknown or dangerous ingredients and are manufactured under unknown or unregulated conditions that can put consumers at risk for side effects.