The party was attended by an estimated 2,000 supporters and filled a sports complex in Metro Manila, the area around the capital.
Packed meals of adobo, a Philippine meat dish, with egg were the suspected cause of the illnesses.
In a statement, Marcos’s son, Ferdinand Marcos Jr., said the organizers were getting to the bottom of the issue. “We have reached out to those affected and are taking care of them,” he said. “I [offer my] apologies and ask for your understanding at this time.”
The celebration also featured birthday cakes that depicted government facilities raised during the two-decade rule of Imelda Marcos’s late husband, Ferdinand Marcos.
Despite the scramble, local news media reported, the party went on. Reporters were not allowed to cover the concert that followed.
Former Philippine dictator Ferdinand Marcos and his family were found to have pilfered up to $10 billion from government funds during his rule. Imelda Marcos, a former beauty queen, gained a reputation for her fondness of luxury, which translated to excessive shopping sprees and thousands of pairs of shoes.
After growing frustration with corruption and human rights violations under her husband’s rule, the family was ousted in the 1986 “People Power” revolution.
Since being allowed to return to the Philippines from exile in Hawaii in the early 1990s, the Marcoses have staged a comeback in local politics. Imelda Marcos’s daughter Imee Marcos won a senatorial bid during midterm elections in May, while Marcos Jr. is still pushing an electoral protest against Vice President Leni Robredo from 2016, when he finished second to her in voting. (In the Philippines, presidents and vice presidents run on party tickets but are elected separately.)
Imelda Marcos served as a congresswoman during the last term. Last year, she was found guilty of graft, based on an indictment dating to 1991 — but she posted bail and has avoided prison.
A previous version of this story gave an incorrect figure for the number of people hospitalized. It has been updated.