Brazil's swimming confederation suspended Fabiola Molina for two months for using a banned stimulant, excluding her from next month's world championships.

The confederation said in a statement Tuesday that 36-year-old Molina tested positive for methylhexaneamine during an April event in Rio de Janeiro.

Molina said she mistakenly ingested the substance, which is included in many dietary supplements and cold medications and was added to the banned list of the World Anti-Doping Agency last year.

"The presence of a banned substance should not be synonymous with doping," Molina said in a statement. "I recognize that due to negligence I ingested a substance that is not allowed in competition and that I did not intend to obtain performance gain."

Because of the suspension, Molina won't take part in the upcoming world championships in Shanghai, and has also lost the time that had qualified her for the 100-meter backstroke at the 2012 London Olympics.

Jorge Souza Santos, spokesman for the Brazilian Aquatic Sports Confederation, said Molina at least another four meets in which to qualify for the Olympics.

The confederation had notified swimming's international governing body, which will make the final decision on the suspension.

Molina took part in the 2008 Olympics and was a bronze medalist in the 50 backstroke at last year's Pan-Pacific Swimming Championships. She also won bronze in relays at the 1995 and 1999 Pan Pacs.

Methylhexaneamine had led to some high-profile and contested doping cases recently, including those of footballer Kolo Toure and South African rugby union players Bjorn Basson and Chiliboy Ralepelle.