Since recreational weed went on sale in Illinois three weeks ago, long lines have formed outside dispensaries, stores have established buying limits, and some have run out of product.

All that was expected, based on what’s happened as other states legalized cannabis. But there’s also been a less-anticipated result: More people want medical marijuana cards.

More than 2,570 people applied for medical cards between Jan. 1, when recreational sales started, and Jan. 17, according to the Illinois Department of Public Health. That’s a nearly 34% increase over Dec. 1 though 17.

Included in that uptick, analysts said, are people interested in using it for medical purposes now that it’s legal. The increase also is driven by consumers looking for a way around sky-high taxes attached to some products.

Medical marijuana has been available in Illinois since late 2015, and about 100,000 Illinois residents already have the medical cards that were needed to buy it at dispensaries. Getting a card can take weeks, but once patients submit the documentation to the state, they are granted provisional access to buy it.

Boosting the ranks of medical customers will further strain Illinois’ nascent recreational weed market, and could mean more customers who don’t have a card leave dispensaries disappointed and empty-handed.

That’s because cardholders typically skip the line and the law requires dispensaries to have enough product for patients — a critical incentive amid statewide shortages that have halted recreational sales at some shops.

Doctors around the state who certify medical marijuana patients immediately noticed the swell in interest after recreational marijuana became legal.

“We predicted that there would be a bump in patient load for cannabis certification, but not the extent we are seeing,” said Dr. Rahul Khare, CEO and founder of Innovative Wellness, which certifies patients for medical cannabis.

The practice in Chicago’s Lincoln Park, which also consults with patients on how to best use marijuana, is seeing about 150 patients per week, up from 80 to 90 before Jan. 1. It has brought on extra staff members and added appointment times to handle the surge.

Chicago resident Dana Balkin had her second appointment at Innovative Wellness Tuesday, and is set to apply for her medical card. Balkin has Postural Orthostatic Tachycardia Syndrome, which causes an abnormal heart rate when she stands. That often results in severe nausea and dizziness, which can only be relieved by lying down, she said.

“There was never anything that worked for the nausea,” said Balkin, 24.

But last year while visiting Las Vegas, where recreational weed is legal, she went to a dispensary to buy marijuana. When she experienced a bout of nausea, the marijuana treated her symptoms. On Jan. 2, she was in a dispensary in Chicago, buying weed in her home state.

“Once they made it recreational, it just got so much more approachable to me,” Balkin said. “They had a table set up telling people about the benefits of getting your medical card, about how you don’t have to wait in line.”

“The biggest thing is not waiting in lines,” she said. “Waiting in lines is what makes me the sickest.”

To get a card, patients must have a medical professional certify that they have one of about 50 qualifying conditions. A doctor must have a physician-patient relationship with the patient to certify them, assess their medical history and have recently conducted an in-person exam.

Patients also must pay a $100 to $250 application fee to the state, depending on how long they want the card to remain valid.

The fees and medical visits could make financial sense, depending on how much marijuana someone buys, since patients pay less taxes than recreational consumers.

Recreational cannabis taxes vary from 10% to 25%, depending on the product’s potency. They are also subject to state and local taxes, plus municipalities can add another 3% tax.

Chicago levied a 3% tax, beginning Jan. 1. Cook County recently approved a 3% tax to take effect this summer. Add that to the city’s 10.25% sales tax, and recreational marijuana purchased in Chicago could be taxed as high as 41%.

Medici Health Care is seeing about 300 people a week at its offices in Wicker Park and Andersonville, up from about 180 before recreational sales started. Some of those are patients who let their medical card expire and need to get re-certified. Others are new patients who tried recreational marijuana and realized the benefits of getting a card.

“They experimented recreationally and they think, this worked for my depression, my migraines, my PTSD, whatever, and they want to see the doctor,” said Dr. Mauricio Consalter, Medici’s medical director.

Other states have seen patient counts increase and decrease following recreational sales, but analysts say tax breaks have been a driving factor.

Patient count went up during 2014, the first year of recreational sales in Colorado where patients avoid a 15% excise tax on weed. The numbers have since declined, but Illinois residents have a greater incentive to get their medical cards, said Tom Adams, managing director of industry intelligence at cannabis research firm BDS Analytics.

“If you’re being spared 20 or 30% cost on an edible and concentrate by being a medical patient, then you’ve got a real strong motivation to get a card,” he said.

Illinois’ medical marijuana program last year doubled in size, to about 100,000 patients, after fingerprinting and background check requirements were lifted, the list of qualifying conditions expanded and people prescribed opioids were given access to medical marijuana.

The increase in patients contributed, in part, to a statewide marijuana shortage. Some medical patients say dispensaries were running low on weed for months before recreational sales started.

Earlier this month, the state warned dispensaries that they are required by law to keep enough product on hand for medical patients.

Veriheal, another company that certifies medical patients, also saw a bump in business at its three Illinois locations. But it’s not just people who want their cards, said Sam Adetunji, managing partner at the Washington, D.C.-based company. Many just want to know more about how weed might affect them.