A bid to expand the list of diseases that could be treated with medical marijuana failed by one vote Tuesday in the Louisiana Senate.

The vote was 19-16, one shy of the minimum needed, and followed emotionally charged arguments on the topic.

The measure, Senate Bill 271, could return for a second vote as soon as Wednesday, according to the sponsor.

Four senators did not cast ballots.

Sen. Francis Thompson, D-Delhi, denounced the measure.

“I am going to tell you, I don’t want my children, my grandchildren or my great grandchildren or anyone that comes after me taking marijuana,” said Thompson, a state lawmaker for four decades.

“I just don’t believe we ought to be headed this direction, with all the drug problems we have,” he said. “I have never in my life had someone ask me about legalizing marijuana.”

But state Sen. Fred Mills Jr., R-Parks, sponsor of the bill and a pharmacist since 1976, was just as passionate in support of his proposal.

“I could tell you story after story, phone call after phone call, visit after visit, of parents who come to my place of business, to show me children, and to say, ‘When can I get this product, my doctor wants to prescribe it. When can I get it?’ ” Mills said.

Mills also disputed arguments that approval of the bill would pave the way for an ever-expanding list of diseases eligible for marijuana and more health care providers who would be authorized to do so.

“We are not opening a door,” he said. “We are finding that ideal balance that we strive to find every day.”

State law already allows medical marijuana to be prescribed for glaucoma, symptoms stemming from chemotherapy and spastic quadriplegia.

The bill would add, among other illnesses, cancer, being HIV positive, AIDS, cachexia, seizure disorders, epilepsy, Crohn’s disease, muscular dystrophy and multiple sclerosis.

The treatment would be in the form of cannabis oil, and it would have to be recommended by a physician, as opposed to being prescribed because it’s illegal for doctors to prescribe marijuana.

The legislation won approval without objection last week in the Louisiana Senate Health and Welfare Committee.

Sen. Danny Martiny, R-Metairie, criticized the plan.

Martiny conceded that some health problems can be eased with medical marijuana. “But we are missing the point that this is an illegal drug,” he said.

Sen. Jay Luneau, D-Alexandria, said he came across research that said medical marijuana can help children with severe epilepsy not responding to other treatments.

Mills said he took steps to address concerns of law enforcement and how the marijuana would be prescribed.

Mills also said a lengthy set of rules would be hammered out to avoid abuses.

“Let’s remember, at the end of the day, our job is to protect the safety, health and welfare of the patient,” he said. “This bill does exactly that.”

Thompson, a state lawmaker since 1975, disagreed.

“It will be like any other vice,” he said. “It will grow legs. It will not be what you will be proud of.”

Follow Will Sentell on Twitter, @WillSentell.

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