Kansas Sen. Pat Roberts’ re-election campaign is questioning the professional ethics of his tea party foe in the state’s Republican primary.

The Topeka Capital-Journal reports that Roberts spokesman Leroy Towns attacked challenger Milton Wolf over Physician’s Own. The now-defunct company registered in Texas sold herb, vitamin and mineral supplements.

Records available online from the Texas secretary of state’s office show it formed in 2000 with Wolf as president. Its website included a slogan saying, “Real Doctors. Real Credibility” and an “ask Dr. Wolf” link.

Towns noted that Wolf wasn’t licensed to practice medicine in Kansas until 2004. Also, Towns said Wolf specialized in radiology, not nutrition.

Wolf spokesman Ben Hartman declined to talk about the company but accused the Roberts campaign of trying to smear Wolf.