Twin brother pediatricians from the northern US state of Ohio face trial for allegedly using their practice to molest boys and teenagers for more than 20 years, prosecutors said on Tuesday.

Mark and Scott Blankenburg, 53, collectively face 76 charges of engaging in sex crimes with minors at their practice in the industrial city of Hamilton, sometimes paying the victims some $US200 ($A225), prosecutors said.

The counts also involve drug trafficking, child pornography, bribery and money laundering.

Mark Blankenburg, whose trial opened on Tuesday, slipped money and prescription drugs to some of the patients after each episode, said Assistant Prosecutor Lance Salyers. Some of the abuses date back to 1987, according to authorities.

"Dr Blankenburg, for about 20 to 30 years now, has been driven by a specific sexual appetite for teenage boys," Salyers told jurors, according to the Dayton Daily News.