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A crack pipe vending machine for addicts sounds like the punch line of a bad joke—but the same kind of ridicule has been lobbed at many measures to fight drug addiction and related harm that have now proven to save lives. From needle exchange programs for HIV prevention to providing heroin to addicts, and from supervised injecting rooms to “wet houses” where homeless alcoholics are given free booze, approaches that seem to “enable” users are in fact effective in helping them to survive and recover.

Crack pipe vending machines were first introduced six months ago in Vancouver by a drug program, and a second one was added earlier this week. In this case, supporters believe that reducing the sharing of crack pipes will reduce the spread of diseases like Hepatitis C, though there is little published data on the question. “There’s no evidence one way or the other,” says Keith Humphreys, professor of psychiatry at Stanford and former Senior Policy Advisor for President Obama’s Office of National Drug Control Policy, better known as the “drug czar’s office.”

Harm reduction—the idea that drug problems can be addressed by reducing drug-related harms like overdose and disease even if users don’t become totally abstinent—became a major but controversial trend in drug policy at the height of the 1980s AIDS epidemic. Vehemently opposed by the Bush administration, which banned federal funds for such programs—and even by President Clinton, who later apologized for being wrong—harm reduction programs continued to spread because the data consistently showed reductions in infections without the feared increases in drug use.

Needle exchange, for example, which first began in the 1980s, has been found to be effective at fighting HIV by every public health organization that has investigated the method, including the World Health Organization [PDF], the Centers for Disease Control [PDF], and the Institute of Medicine. “Relative to other things we do in public health—like wearing seatbelts or fluoridation of water—this is a well-supported intervention and does reduce the prevalence of HIV in the population. That’s really valuable,” says Humphreys, adding that it is probably not as effective in preventing Hepatitis C because that virus can survive for much longer outside the body.

There is also significant evidence to support giving heroin to heroin addicts who have repeatedly been failed by other treatments like methadone maintenance and Twelve-Step programs. A 2012 Cochrane Review, considered to be among the highest levels of medical evidence, examined data from countries that have trialed or currently provide heroin maintenance treatment, including Great Britain, Canada, Switzerland, and Germany and comes down in its favor. The authors write that heroin provision “may help [addicted people] to remain in treatment, limit the use of street drugs, reduce illegal activities and possibly reduce mortality.”

MORE: Heroin Cheaper, More Effective than Methadone For Hard Cases: Study

And, though it sounds hard to believe, needle exchange can also be a pathway to abstinence or medication-assisted treatment. Far from making users more likely to continue to inject or increase their drug use, research shows that such programs actually increase the number of addicts who seek abstinence treatment or maintenance that will allow them to stop injecting.

There are two major theories about why this occurs. One is that taking action and using clean syringes to reduce drug-related harm increases drug users’ confidence that they can make other changes. The other is that by offering help without demanding anything in return, the staff of these programs (many of whom are recovering addicts themselves) inspire change. “The experience of being loved or cared about in a way that is something other than instrumental can be very powerful,” says Humphreys.

At Insite, North America’s only supervised injection center, addicts can get clean needles and shoot up under medical supervision. It also has a detox program. “In itself, harm reduction is valuable regardless of whether it leads to abstinence,” says Gabor Maté, a Canadian addiction doctor and author of In the Realm of Hungry Ghosts, about his experience working at Insite, “Had [my patients] not had contact with Insite and the experience of acceptance and nonjudgment, they would not have ended up in detox” Maté says.

There are more than two dozen peer-reviewed studies of injection rooms, Maté says, “all showing positive effects in terms of reducing disease, fewer medical costs, increased prosocial function—absolutely nothing negative.” Humphreys, however, finds the data here less convincing than for needle exchange alone or opioid maintenance because, he says, there are not as many good studies by objective researchers.

Providing free heroin leads to abstinence more often than one might expect. One Swiss study found that 40% of participants sought abstinence treatment as a way of completing the program, despite the fact that it wasn’t required. This may be because heroin addicts’ lives tend to be occupied and defined by the difficult quest for drugs and the hustling needed to get money for them. When the drugs are easy to get, their lives can seem empty and boring. But with support, this extra free time can pave the way for either abstinence or employment, or both. In fact, some of the heroin studies have shown that employment rates as much as double, although they remain low and the rise is not much greater than that seen with methadone treatment alone.

Though newer, alcohol harm reduction also appears to be promising. One study, published in the Journal of the American Medical Association, found that a Seattle “wet house” program offering both booze and housing to chronic alcoholics cut public spending on policing and medical care for them by 53%, saving the city an average of $2,449 per person per month. Not only that, but the participants actually reduced their drinking from an average of 16 drinks per day to 11.

“It removes anxiety, provides acceptance, and reduces isolation,” says Maté, “When they are less anxious and less isolated and feel more accepted, there is less need to use. [Excessive] use of substances is about trying to adapt to unbearable emotional and social situation.”

Humphreys cautions that it is not yet clear whether “wet houses” have negative effects on the street alcoholics who aren’t offered them. They are currently being considered in San Francisco to house the most chronic alcoholics who cause the biggest public nuisance, and he worries that this might provide an incentive for people to get worse so they can get housing. “I’d like an apartment in San Francisco. And free wine would be awesome,” he jokes.

While harm reduction may make politicians queasy, the data clearly supports the most commonly used measures like needle exchange, methadone, and Suboxone, and so far suggests possible benefit from more controversial measures like heroin provision, safe injecting rooms, and “wet houses.” It may be a while before you see a crack pipe vending machine side-by-side with a soda vending machine, and they still remain to be properly evaluated, but it’s probably too early to dismiss the notion outright.

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