Olympic champion Dawn Harper-Nelson serving 3-month doping ban

Dawn Harper-Nelson, an Olympic 100m hurdles gold and silver medalist, is serving a three-month ban after taking a prescribed medication and failing to learn that it contained a banned substance.

Harper-Nelson tested positive for the banned diuretic hydrochlorothiazide and related metabolites on Dec. 1, according to the U.S. Anti-Doping Agency:

Harper-Nelson’s explanation that her positive test was caused by a blood pressure medication she was prescribed by a physician to treat hypertension. Harper-Nelson further explained that she made efforts to determine if the medication contained prohibited substances; however, due to using partial search terms, those efforts were unsuccessful.

Her three-month ban began Dec. 1, meaning she will miss no major outdoor meets.

Harper-Nelson won the 2008 Olympic 100m hurdles title and took silver behind Sally Pearson in 2012. She failed to make the Rio Olympic team, getting eliminated in the Olympic Trials semifinals.

The U.S. trio in Rio swept the medals -- Brianna Rollins, Nia Ali and Kristi Castlin.

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