BOSTON — Massachusetts voters may have enthusiastically approved the legalization of medical marijuana, but that hasn’t stopped communities around the state from rushing to amend their zoning regulations to make sure marijuana dispensaries are banned or restricted in their towns.

Although the law allowing the use of marijuana for patients with serious medical conditions goes into effect Jan. 1, the state Department of Public Health has until May 1 to issue regulations on who will run the dispensaries, who will work there and how they will be operated. DPH must also decide what constitutes a 60-day supply patients can receive.

While the DPH works on the regulations, some cities and towns are working to keep out dispensaries, or “pot shops” as they are often called. In Wakefield and Reading, the towns have already approved zoning changes to ban dispensaries.

“People are concerned about how broad the law was written and that the dispensaries could be used by more than just people with medical issues,” said Ruth Clay, the health director for Wakefield, Reading and Melrose, a city that is also working to pass a ban on dispensaries.

Clay said her communities receive a significant amount of state and federal grants to run substance abuse programs and are concerned that having a marijuana dispensary in town could “send a mixed message to youths.”

The law approved through Question 3 on the November election ballot eliminates civil and criminal penalties for the use of marijuana by people with cancer, Parkinson’s Disease, AIDS and other conditions determined by a doctor.