HARTFORD, Conn. – Connecticut lawmakers’ approval of the use of medical marijuana includes strict regulations for the cultivation and distribution in an attempt to avoid problems other states have run into when legalizing the plant for medical use.

The bill, passed early Saturday by the state Senate, is headed to Democratic Gov. Dannel P. Malloy, who said in a statement that he plans to sign it, as he believes the law would “avoid the problems encountered in some other states.”

Sixteen states, including Maine, and the District of Columbia have laws authorizing the use of medical marijuana. Since California passed the country’s first such law in 1996, states have struggled with disorganization and clashes with the federal government, which considers the drug illegal and of no medicinal value.

“Everything from California back is trying to get away from chaos,” said Allen St. Pierre, the executive director of the National Organization to Reform Marijuana Laws.

Advocates say the Connecticut proposal goes further than any other state in regulating the drug.

Under the legislation, marijuana would be sold in multiple forms at dispensaries, which must have a licensed pharmacist on staff. It would be marketed only to patients authorized to use it. The measure also outlines diseases that would be treated by the drug, establishes a registry for patients and caregivers and restricts cultivating the plant to growers with permits.

“Experience has shown that having statewide structures in place makes it easier for everyone to understand what the rules really are,” said Alan Shackelford, who serves on a state advisory work group for medical marijuana in Colorado and helped advise Connecticut lawmakers on their proposal.

Opponents in Connecticut, however, point to a letter from U.S. Attorney David Fein, who wrote that while the Department of Justice would not go after seriously ill patients who use the illegal drug, federal laws would be enforced against those who manufacture and distribute it.

“The violation of a federal law to me is a big stop sign and I just can’t bring myself to go through it,” said Rep. Steven Mikutel, D-Griswold, who voted against the legislation when it passed the state House.

In addition to federal efforts to shut down dispensaries in California and, to a lesser extent, Colorado, problems with regulation have arisen in states where the drug was legalized through ballot initiatives and the system was implemented without regulations in place, advocates say. Likewise, some states don’t allow medical marijuana dispensaries and patients are left to grow their own.

Because of this, several states have been taking steps to strengthen regulations.

Colorado imposed tight regulation and state government control over dispensaries in 2010. New Jersey and Delaware also have passed laws to strictly regulate medical marijuana.

California state Sen. Mark Leno said he was working to enact legislation that would further clarify that care providers be exempt from prosecution for providing the drug to patients.