Russia, who will host the next winter Games in the Black Sea resort of Sochi in 2014, has been trying to root out cheats before the February 12-28 Vancouver Games with Alena Sidko, one of their top cross-country skiers, the latest offender.
"I understand that people are worried by the numbers," International Olympic Committee president Jacques Rogge said.
"We have indeed been alerted by the number of positive cases. It is legitimate to be worried. I was puzzled by the numbers."
Rogge said he had raised the issue in meetings with Russian sports officials and the country's President, Dmitry Medvedev, recently.
"We have alerted Russian authorities and we now expect them to comply," he said.
"I insisted (in talks with president Medvedev) on the need to have a strong action on doping and he promised that he would launch that and he was very explicit in public declarations."
Russia has seen a spate of positive tests prior to these Winter Games with the country's anti-doping agency under mounting pressure to crack down on athletes taking performance-enhancing drugs.
Among the Russian athletes taking part in Vancouver is Olga Medvedtseva, formerly competing as Olga Pyleva, who had won the 15km individual race silver medal at the 2006 Olympics before failing a doping test and having her medal taken away.
She sat out a two-year ban before returning to competition.
Rogge defended her participation saying she had paid the price for her doping offence.
Medvedtseva is fortunate to compete though because under a new rule brought in two years after she was caught, athletes who are banned for six months or more for a doping offence are automatically excluded from the next Olympics.