Proposed limitations on how much medical marijuana Ohio patients could possess and purchase would be one of the most stringent in the country.

Patients could possess and purchase up to 6 oz of marijuana products or plant material comprising the equivalent amount of THC in a span of 90 days. That sets Ohio on level with New Jersey and Washington D.C. as the most restrictive states among 13 regulators compared Ohio with.

Ohio’s medical marijuana law permits patients with 20 medical conditions to purchase and use marijuana if recommended by a physician. Smoking the plant isn’t permitted, but dispensaries can sell plant material and oils for vaping, tinctures, patches and marijuana-infused oils and foods.

The law restricts patients to purchasing and possessing at most a “90-day supply,” but does not define how much that is. On Thursday, the Ohio State Board of Pharmacy released draft rules detailing the allowable amounts.

Most states restrict the total amount of “usable marijuana” someone can purchase, whether that is plant material or marijuana-infused cookies. Ohio regulators are proposing restricting supply by product’s amount of THC, the psychoactive compound in marijuana that creates a high.

Of the 28 medical marijuana states, Ohio would be the first to compute limits in this manner.

“I believe this is the right approach because we’re in the middle of the pack of states that have adopted this,” Steven Schierholt, executive director of the State Board of Pharmacy, told the Ohio Medical Marijuana Advisory Committee on Thursday. “We’ve benefited form what other states have done and have the benefit of their successes and failures.

Pharmacy board officials said after looking at other state policies, clinical research and data about adverse effects, the amounts were determined.

Chris Lindsey, senior legislative counsel for pro-marijuana group Marijuana Policy Project, said the first recommendations were not excessively restrictive. He said supply and dosage are tricky limitations for the state to establish because physicians can’t prescribe how much patients should consume.

Patients could mix and match products but each amount added together couldn’t exceed a total 90-day supply. So if a patient purchased 70 days worth of plant material, they couldn’t purchase more than 30 days worth of edibles or vaping oils.

The proposed limitations:

6 oz of plant material with THC levels below 23%
4 oz of plant material with THC levels above 23% — the maximum level permitted is 35%
40.5 grams of THC in vaping oils (220 mg per day)
19.8 grams of THC in transdermal patches (450mg per day)
9 grams of THC in edibles, oils and tinctures taken orally (100 mg per day)

Plant material was split in two classes because research reviewed by the pharmacy board revealed THC was more effective with fewer side effects at levels below 23%.

An ounce of plant material weighs about 28 grams and might be properly used in anywhere from 30 to 50 rolled joints.

The proposed rules would likewise impose a $100 fee on every strain or dosage of a product, probably paid by the product manufacturer. Advisory committee members expressed concern about patients having the capacity to afford the products.

Schierholt said they want feedback and don’t want to drive up prices for patients.

Public opinion is being accepted on the proposal through March 10. The rules will go through two more phases of review and comment before being finalized.

Lindsey said state officials have done an excellent job drafting regulations for a workable program that serves patients.

“There have been many ways they could have derailed this procedure and they haven’t done that,” Lindsey said.