Source: drug named that triggered positive test of Mayfield:

Jeremy Mayfield tested positive for methamphetamine during a random drug screening May 1 at Richmond International Raceway, ESPN The Magazine has learned from two independent sources. In court documents filed in the past two weeks (Mayfield sought a temporary restraining in order to return to the track; NASCAR countersued), it was revealed that Mayfield had admitted ingesting a double dosage of Claritin-D [note: which contains pseudoephedrine which is used in the illicit manufacture of methamphetamine], an allergy medication, and the prescription drug Adderall XR immediately prior to the Richmond drug test conducted for NASCAR.(full story at ESPN the Magazine)(6-9-2009)