Medical marijuana is legal in 23 US states including New Jersey but Facebook has taken down several pages that advertise and sell the drug, saying they violate the website's rules.
Facebook homepages run by three dispensaries in the so-called Garden State have been shut down, as reported by NJ.com.
Dispensary owners and customers have reacted in anger. Facebook has declined to respond and has referred media to its community standards section.
Several medical marijuana centers, including the Garden State Dispensary, the Breakwater Wellness and Treatment Center and the Compassionate Sciences Alternative Treatment Center in New Jersey said when they tried to use their homepage, they were shown a message that read: "We remove any promotion or encouragement of drug use.”
“Your page is currently not visible on Facebook. It looks like content on your page does not follow the Facebook Community Terms and Standards.”
Facebook does not allow advertisements that promote the sale or use of illegal, prescription or recreational drugs.
Ken Wolski, Chief Executive Officer of the Coalition for Medical Marijuana and a registered nurse in New Jersey, told The Independent it was “entirely inappropriate” for Facebook to shut down these pages.
“These pages do not violate community standards, they reflect community standards.”
“Marijuana was legalized over six years ago - the federal government has not intervened [with state law] so why has Facebook intervened?” he added.
A spokeswoman for the Washington-based Marijuana Policy Project said in a statement: "While Facebook is a private company and has the right to control what businesses advertise on their site or the content of posts, it makes no sense for them to censor content related to medical marijuana. Marijuana transactions cannot take place on Facebook, so the company would not be breaking any federal laws, and many dispensary Facebook pages provide useful information for people looking to learn more about a medicine that is legal in their states."
Mr Wolski added that about 5600 patient ID cards have been issued in New Jersey for patients to legally access medical marijuana, but some people still use the drug illegally because their health condition is not yet recognized.
“All forms of chronic pain are excluded except that caused by cancer or HIV aids - it’s an arbitrary limitation and has no scientific basis," said Mr Wolski.
Medical marijuana is also proven to help treat neurological conditions such as multiple sclerosis, muscular dystrophy and ALS, as well as Parkinson's disease.
Possession and production of marijuana is illegal under federal law but it is legal in 23 states.
Dispensaries in Maine and Washington have also reportedly complained about their Facebook presence being disconnected.