The 30-year-old, Somalian-born athlete completed the first 20km in 58 minutes 30 seconds, before bowing out while placed fourth in the field.
Farah, who won the New Orleans half marathon earlier this year, has never gone the full distance, however he believes yesterday’s experience will stand him in good stead to be competitive in 2014.
“Next year I’ll come and do the full marathon,” he said. “I’ve learned the biggest lesson of my life. If I had come here next year and made a mess of the race I don’t think I could have dealt with that.
“The biggest challenge I had was picking up the right drink, I made a mess of that.”
All of the pre-race talk surrounded the safety of the event after three people were killed and 176 injured by bombs in Monday’s Boston Marathon.
But, with an increased police presence allaying security fears, spectators turned out in their droves to cheer on the 35,000-strong field, who observed a 30-second period of silence before the start of the race to remember the victims of Monday’s tragedy.
American Tatyana McFadden followed up her victory in Boston to win the women’s wheelchair race, as the defending champion, Shelly Woods, finished fifth.
The elite men’s race was won by Tsegaye Kebede, who sped past course record holder Emmanuel Mutai on the Mall to win for the second time in the capital in 2:06.04.
Kenya’s Priscah Jeptoo clocked 2:20.15 to triumph in the elite women’s race, which earlier saw London 2012 gold medal winner Tiki Gelana suffer an injury after colliding with wheelchair racer Josh Cassidy at a drinks station.
Six-time winner of the men’s wheelchair race, David Weir, had to settle for fifth in a race won by Australia’s Kurt Fearnley. However, Weir played down any talk this year’s London Marathon being his last.
“You can’t win all the time,” said the 33-year-old.
“I’ll bounce back.”