By Derrick Blakley

(CBS) — Medical marijuana is one step closer to reality in Illinois after a panel of lawmakers approved regulations for patients, growers, and retailers.

But even after it becomes legal January 1, there still may not be any to buy, reports CBS 2’s Derrick Blakley.

Approval on medical use of pot came, appropriately, from the Joint Committee on Administrative Rules

“This is the most highly regulated, highly controlled, safe medical marijuana law anywhere in the country,” said State Rep. Lou Lang, (D-Skokie).

Patients with last names starting A to L can apply to the public health department starting in September. Patients with last names starting N to Z, can apply starting November. But you’ll also need a letter from your doctor.

“That’s why patients should get about the business of talking to their physicians right away,” said Lang.

21 companies will be growing the pot. Grand Prairie Farms wants to be one of them, using giant indoor spaces.

“190 thousand square feet is about our target,” said Bryan Wilmer of Grand Prairie Farms.

That is actually bigger than the size of a Target, more like the dimensions of a Walmart Superstore. But first, the growers have to win the licenses and actually get rolling, so to speak.

“We’re expecting even once licenses are issued for cultivation centers, a four to six month time for cultivation to actually occur,” said Ali Nagrib with the Illinois chapter of NORML, the National Organization to Reform Marijuana Laws.

Which means, although medical marijuana will be legal January first, it probably won’t be available.

“We expect it will take at least a few months for any applicant to get up and running for a cultivation center, given they’re growing a product that isn’t currently being grown,” said Bob Morgan of the Illinois Department of Public Health.

Patients suffering from 39 designated conditions including cancer, glaucoma, lupus and MS will be able to use medical marijuana.

While patients see relief, businesses see a gold mine. One potential grower believes Illinois will be a $900-million market in the first year.

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