The number of medical marijuana dispensaries in Massachusetts, a state that has struggled to implement the medical marijuana program since voters approved it in 2012, is increasing.

A dispensary is open in Brookline, run by New England Treatment Access, and another dispensary, run by Patriot Care, is holding its grand opening in Lowell on Tuesday, Feb. 16.

New England Treatment Access, which has a medical marijuana dispensary in Northampton and a cultivation facility in Franklin, sent an email on Friday notifying patients that their Brookline shop is open.

Aside from NETA's Northampton and Brookline locations, dispensaries, owned by other companies, also opened in Brockton (run by In Good Health, Inc.), Ayer (Central Ave. Compassionate Care, Inc.) and Salem (Alternative Therapies Group, Inc.).

NETA located its Brookline dispensary inside the renovated Brookline Bank building on Route 9.

"For the first few weeks, we will be operating on an appointment-only basis," the company said in an email.

New England Treatment Access, which has a medical marijuana dispensary in Northampton, has opened one inside an old bank building in Brookline, just outside of Boston. (Courtesy: NETA)

Like the Northampton dispensary, the Brookline location's menu includes items named "Facewreck," "Amnesia Haze," and "Sour Tsunami."

Patriot Care is opening its Lowell location on Tuesday, and according to the State House News Service, no appointment is required.

"I know what I've heard about the other dispensaries, and I think people have been driving long distances to be able to get to the other dispensaries," Patriot Care CEO Bob Mayerson told the wire service.

"There's almost 20,000 patients registered with cards right now in Massachusetts, and there's only four or five dispensaries open," he added.

Patriot Care is also looking to open locations in downtown Boston, at 21 Milk St., and in Greenfield, at 7 Legion Ave., later this year.

Registered medical marijuana patients are allowed to have a 60-day supply, equaling 10 ounces.

According to data from the state Department of Public Health, which is regulating the medical marijuana program, there are 19,279 registered and certified patients, as of the end of January 2016.

Since the start of the program, the amount of medical marijuana sold in ounces is 17,900, according to the same DPH data.