Call it “the Gateway Bill” — or “Cheech and Chong’s Law.”

Albany is looking at legalizing “medical marijuana” — and then making it unique among prescription drugs by taxing it.

Maybe it’s a step on the way to legalizing pot altogether — or maybe to taxing all medications.

Revenue projections from prescription pot are part of the state Senate’s budget for 2010-11 — and the bill to legalize and tax it looks to be on the fast track.

The bill, sponsored by Senate Health Committee Chairman Thomas Duane and Assembly Health Committee Chairman Richard Gottfried (both Manhattan Democrats), passed the Senate Code Committee last week and will now go to the full Senate for a vote.

Albany would collect in two ways. First, the state Health Department would issue licenses to specific dispensaries and growers; the Senate budget projects this could yield as much as $15 million for the state next year alone. But the real gold is in the sales tax on every dope purchase — which could bring in up to $500 million for Albany’s coffers.

But weed would be unique in having a sales tax attached to it. The purchase of prescription pharmaceuticals, and even some over-the-counter drugs, is generally exempt from taxation because of their medicinal value.

As the Tax Foundation’s Bill Ahern asks, “If they are going to tax marijuana, isn’t that just like an admission that it has no medical value?”

Alternately, of course, perhaps state lawmakers figure this is a good test for taxing all medicines. Not a good idea, and not likely — on the other hand, they might decide it’s a good way to close those multibillion-dollar budget gaps. And the taxes could start small . . .

But it’s much more likely to be just a step toward broader legalization. In other states with medical-MJ laws, potheads find plenty of ways to get prescriptions.In California, it’s a matter of finding the right doctor who will then prescribe pot to treat such varied symptoms as general anxiety, trouble sleeping and other vague “nervous conditions.”

And it’s hard to believe New York’s state Health Department — which notoriously can’t even police nursing homes — is going to do much to stop the same thing from happening here.

California, meanwhile, might make the leap from prescription pot to legalization. After a decade, the Golden State is only getting $100 million a year in revenue from its pot tax. Democrat Assemblyman Tom Ammiano proposed a bill to fully legalize marijuana — which the state’s tax collectors estimate would bring in about $1.3 billion a year. The bill failed to pass — but a legalization measure will be on the ballot in November.

Voters might approve it just for the revenue. “The state of California is in a very, very precipitous economic plight. It’s in the toilet,” says Ammiano. “With any revenue ideas, people say you have to think outside the box . . . and I feel that the issue of the decriminalization, regulation and taxation of marijuana fits that bill.”

Back to New York, where the Senate bill would plainly tax “medical” marijuana as the state does cigarettes and alcohol, with consumers paying a premium for the privilege. Sure looks more like a “sin tax” than a compassionate act for people in chemotherapy and others with real illnesses.

Maybe New York is ready for a stealth path to legalizing pot: It’s already decriminalized — or largely overlooked by the cops — in much of the state. Full legalization would simply mean that Albany makes some of the profit off what’s now a huge black market.

But if we’re going to go there, let’s be honest about it — and not pretend “medical marijuana” is about the sick.

awschachter@nypost.com

