Love potions have been a plot point in fairytales for centuries. Now, thanks to dramatic advances in our understanding of the neuroscience behind love, they’re close enough to reality to be studied by Oxford University researchers.

Anders Sandberg, a neuroethicist at Oxford University’s Future of Humanity Institute, will discuss the role of romance drugs at an upcoming Institute of Art and Ideas conference “Love in the Time of Tinder”. He says that while we can’t buy romance pills yet, it’s only a matter of years before they exist. His work combines neuroscience and philosophy to unpack the ethical consequences of such pills, and just how they’ll fit into our lives.

“All our emotions are built on the foundations of neuroscience,” Sandberg says—whether that’s fear or anger or love. Recently, neuroscientists have begun to map out just what happens in the brain when we’re in love, bringing us closer to artificially recreating those neurochemical processes. “While there’s still not anything you can find in the supermarket or approved, we’re getting towards the point where they probably will show up,” he says.

Neuroimaging studies of brains show that love is, well, extremely complicated. (No surprises there.) Different subsystems of the brain are involved in that initial lustful attraction, the rush that comes when you fall in love, and then the commitment and affection of long-term partnership. It’s that last, lengthy phase of love that romance drugs are likely to focus on, effectively re-booting the romance for existing couples.

“It’s very different to the love potion in fairytales where you drink it and then fall in love with the next person who comes in,” Sandberg says. “From an ethical standpoint, that’s very worrisome… I would imagine a future love drug would be something you take together with your partner, and that causes a slow, long-term experience.”

Scientists have identified the brain system behind long-term feelings of romantic love partly thanks to studies of prairie voles (yes, you read that right). There are two closely related species of prairie vole; one is monogamous and the other is not. Key differences in the oxytocin system of these two species suggest that this hormone is crucial to the ability to stay together.

These findings are supported by neuroimaging studies of humans who claim to be in love, which again show that oxytocin is key. (The specific systems activated in the brains of those who are romantically in love overlap with, but are not exactly the same as, the systems involved in parents thinking about their love of their children.)

There are several drugs already available (legally and illegally) that create a release of oxytocin, and there’s likely plenty of informal love-drug experimentation already underway with potent substances such as MDMA or the Amazonian hallucinogenic ayahuasca. “People are trying things that might make sense,” says Sandberg. “Ecstasy is not implausible.” Oxytocin nose spray is another possible option, though there are no definitive studies on the effects of these drugs.

In general, Sandberg believes currently existing drugs have too short-term an effect to be truly effective in boosting romance. A trained therapist would also have to be involved to create the best effect. “You probably want to teach your brain to produce oxytocin when you actually meet your partner,” he explains. “You want to teach the brain: This is the person I’m together with.”

Sandberg expects to see growing numbers of pharmaceutical drugs that affect oxytocin levels, in part because there’s interest in the theory that oxytocin is connected to autism-related disorders.

But while it’s entirely plausible, from a scientific standpoint, that we’ll have approved romance drugs within a decade, do we really want to artificially interfere with love? If a love has faded, perhaps it’s best to move on rather than use drugs to resuscitate it.

In some senses, we already interfere with the pathways of long-term love, argues Sandberg. “Should people having trouble in a relationship go to a marriage counselor?” he asks. “Shouldn’t a marriage just fall apart naturally?… If someone goes away on a romantic holiday that costs a lot of money and comes back with a better marriage, we’d probably say, ‘Yeah, that’s great.’”

But surely there’s a clear line between medicalization and other means of improving a marriage, just as in sports there’s a difference between physical training and using drugs to boost performance? Well, the key concern in the sporting analogy is cheating, says Sandberg. Cheating in how you fall in love doesn’t make much sense: “Could you look at a married couple and say, ‘They cheated”?” he asks. “‘They’re deeply in love but they got to that state in the wrong way. Ha, those losers.'”

The primary focus for romance drugs should be whether they could be a force for good, Sandberg says. To answer that question, it’s important to remember that romantic love isn’t always positive. Indeed, there may be a use for “anti-love” drugs, Sandberg says, to help people leave abusive relationships. A potentially less-ethical use of such drugs would be to help people get over break ups (which, economists have told Sandberg, would certainly increase the liquidity of the dating market).

But aside from clear-cut cases of abuse, it’s often impossible to know whether or not a long-term relationship is worth trying to save. Some couples break up and forever regret it, while others are sad for a while but rediscover their own passions, make stronger friendships, or fall happily in love with someone else.

“If the only thing holding your marriage together is a steady supply of oxytocin, then maybe this marriage is not very good and might be better off cancelled,” says Sandberg. But realistically, he argues, relationships that are that far gone probably won’t be saved by pills. Instead, love drugs would work best as a top-up on romance that’s solid but in need of reinvigorating.

Beyond the requisite drug trials and safety questions, these ethical concerns are likely to delay the introduction of love drugs. “I think in many ways, the drugs might be the easy part,” Sandberg says. “Figuring out how they actually fit into our lives is going to be the great challenge.”