Dozens of protesters lined up outside the Norris center Monday in Naples to rally against Amendment 2.
The proposal needs 60% of the vote to pass in next month's general election. If passed, it would expand the illnesses for which marijuana can be prescribed for. The measure narrowly failed in 2014.
"There's medical marijuana and there are some people who want it legalized for recreational uses," said Marianna Dimurcurio, who opposes the amendment.
Supporters of the amendment say the bill protects that from happening. Doctors who prescribe marijuana to people who don't need it, will be prosecuted.
"If the Florida Legislature has passed any law in the past 6 sessions, that medical marijuana bills were introduced, any law that actually gave patients access to this medicine. We wouldn't be here today," said Raymer Maguire of United We Care, the organization backing the amendment.
Supporters of Amendment 2 say counties and cities will be given the option of banning marijuana grow facilities from operating in their communities.