The World Anti-Doping Agency has adopted a new code that would ban drug cheats for four years, twice the previous penalty.
The revised legislation was unanimously accepted at an international conference in South Africa on Friday.
"The result of this process is that we now have a code which, I believe, offers the best response to combating the scourge of doping," WADA President John Fahey said.
Cheaters would miss at least one Olympics under the new rules. The international Court of Arbitration for Sport rejected a similar proposal several years ago but this one is thought to have a stronger legal basis.
In other anti-doping news, WADA officials said they have completed a review of the troubled Jamaica Anti-Doping Commission and have delivered recommendations to that country's minister of sport.
"WADA is satisfied that the minister has accepted the practical suggestions it made and now looks forward to their full implementation in the coming weeks," a statement said.
Jamaica has seen numerous athletes -- including sprinters Asafa Powell and Sherone Simpson -- fail tests in the past year.