More than 850 tests will be carried out at the world championships in Helsinki between 6 and 14 August. Virtually one in every two athletes will be tested during the competition, the IAAF said in a statement.
Approximately 350 competitors will be blood screened as they enter the athletes' village and nearly 500 tests will be carried out during the event.
About 100 blood tests will also be carried out during the championships for the detection of blood transfusion, haemoglobin-based oxygen carriers (HBOCS) and other substances. HBOCS have been named by many experts as possible performance boosters.
"The IAAF is determined to ensure that these championships highlight our on-going, aggressive commitment to the war on doping," the president, Lamine Diack, said.
"In Paris, at the last edition of the world championships, 405 doping tests were carried out. In Helsinki, in co-operation with the Finnish Anti-Doping Agency, we plan to have the most ambitious and comprehensive system of testing ever activated at a world championships.
"We have increased the testing before, during and after the competition and we will also focus our efforts on education," added Diack.
Meanwhile, China's Olympic champion hurdler Liu Xiang is out of form and unlikely to win gold in Helsinki, according to his coach. Liu was exhausted after running five races in the United States and Europe this year and has been struggling with a knee injury, his coach, Sun Haiping, said.
"Liu Xiang is not as strong as before travelling to Athens for the Olympic Games last year," Sun said. "At that time, he was ready to create miracles in Athens. But now he is not in good form."
Liu, 21, equalled the world record for the 110-metre hurdles at Athens in 12.91 seconds and his showdown with American four-times world champion Allen Johnson is one of the most anticipated races of the world championships, which start on 6 August. Johnson won their most recent duel in New York last month, while Liu was victorious in the previous race in Oregon after his American rival was disqualified.
But they both face a competitive field, which includes France's Ladji Doucoure, in Helsinki. Sun said he would be satisfied if Liu managed to better his bronze medal at the 2003 world championships in Paris.
China's latest sporting hero has been deluged with letters of support . "I tried to write back to a few," Liu, now 22, said via a translator during an interview. "But I had to give up. I would not have been able to do anything else but respond to letters."
Liu's mailbag contained a startling 300 love letters on some days, said his translator, Shelley Peng. All the messages, including the romantic notes, are in storage, waiting for Liu to find an opportunity to read them.