Some had experienced vomiting and hallucinations but none are in a critical condition.
Ms Williams wrote on X, formally Twitter: “Over 60 primary school students had to be taken to hospital. Parents please beware.
“The doctors and nurses are doing all they can to ensure the students recover," adding that several of the children had to be put on an intravenous drip.
“One little boy said he only had one sweetie. That’s how potent this product is. Danger!”
Local news agencies reported that the students are from Ocho Rios Primary School.
A principal told the Jamaica Observer that a “lone vendor” had sold the sweets to its pupils.
Senior Superintendent Dwight Powell, head of the St Ann’s police department, has urged anyone with information to contact the authorities.
Ms Williams posted a photo of the candy package showing a government warning on the back stating, “keep out of reach of children” and “not intended for use by anyone under 21 years of age”.
Each is said to contain 100mg of the psychoactive substance Delta-8 tetrahydrocannabinol (THC) - generally a high dose for an adult.
According to the US Food and Drug Administration (FDA), Delta-8 has “intoxicating effects”.
The sweets, which are not FDA-approved, were produced by a company based in California where cannabis is legal.
Jamaica decriminalised the possession of small amounts of cannabis, also known as marijuana, for personal use in 2015.
However, Health Minister Christopher Tufton told the Jamaica Star that the government did not allow the import of edibles containing drugs.
The incident comes more than a week after around 90 children fell ill in South Africa after eating drug-laced muffins that officials said they had bought from a street vendor.