Tom Hamilton has jetted back to the US due to illness.
Aerosmith are due to play in Manila, the Philippines on May 8 and Jakarta, Indonesia three days later. It is understood that Hamilton will return to the tour once he has recovered from a chest infection, but it has not known when.
Hamilton was forced to take a hiatus from touring in 2006 while recovering from throat cancer, a problem which reared its head again in 2009.
He has previously stated that he requires his throat to be looked at by a doctor every 2-3 months.