Nigerian Osayemi Oludamola was stripped of the women's 100 metres Commonwealth Games gold medal on Tuesday after her B sample confirmed a positive test for a banned stimulant, the Games Federation said.
"The Federation Court determined that Ms Oludamola had committed an anti-doping rule violation and that she be disqualified from the Games and all her competition results at the 2010 Commonwealth Games be nullified," said a statement.
Her compatriot Samuel Okon, a 110 metres hurdler who also tested positive for Methylhexaneamine, waived his right to have his B Sample tested and has also been disqualified, the statement added.
Oludamola was awarded gold in controversial circumstances when Australian Sally Pearson was disqualified for a false start three hours after crossing the line.
Natasha Mayers, who crossed the line third in the blue riband sprint to take St Vincent and the Grenadines' first athletics medal, will now be awarded the gold medal.
Mayers served a two-year doping ban after testing positive for the male sex hormone testosterone in 2005.
The silver medal now goes to Katherine Endacott of England, with Bertille Delphine Atangana of Cameroon taking the bronze.
Methylhexaneamine, a stimulant commonly used in nasal decongestants, was added to the World Anti-Doping Agency's (WADA) banned list this year.
Media reports in Nigeria said Oludamola blamed a toothache remedy for the failed test but Games Federation chief Mike Fennell earlier suggested nutritional supplements might be to blame.
"The same substance is coming up and at this stage I cannot speak very definitively as to where it is coming from but it appears to us that it may be coming from the use of supplements," he said.
Okon finished sixth in the sprint hurdles final last Friday and his failed test was announced on Monday.
"I heard about the second test and as the chef de mission of the Nigerian contingent, I am really concerned," Elias Usman Gora said..
Fennell said 1,200 tests had been conducted at the Delhi Games by the end of Monday.
