Marley's Mellow Mood drink sickened several New Jersey middle school students, the school's cafeteria operator said.
The beverage, which packaging says is not intended for children, contains ingredients such as valerian root intended to promote relaxation and relieve stress.
The school has since removed the product and suspended a manager because the drink was not on the approved list of beverages to be sold.
An investigation is also pending.
"We sincerely regret that this product was sold and that students had an adverse reaction to it," the statement said. "Chartwells takes great pride and care in partnering with our school communities to provide the best school dining experience possible and we take this situation very seriously."
The drink, which features a likeness of Bob Marley, was created in partnership with his family.