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The authors of the new book Love Drugs: The Chemical Future of Relationships really, really want readers to know they have not written a book promoting love potions—drugs that will hypnotize, brainwash, or otherwise ensnare people into being artificially in love (or artificially not in love).

Rather, over the course of some 200 pages, the ethicist Brian D. Earp and the philosopher Julian Savulescu make a measured case that doctors and mental-health practitioners could (maybe, someday) repurpose the known side effects—particularly mood-altering ones—of certain medications and substances as relationship aids. One example from early in the book: Even otherwise compatible romantic partners can be rendered miserable by a big difference in sex drives. If, say, the more desirous partner is already taking a medication, and a different version of that medication is known to decrease sex drive, the authors ask: Would it be so bad for that person to switch versions, in hopes of improving the relationship?

Calling a book Love Drugs—a title that evokes psychedelic, ’60s-era free love and Aldous Huxley’s Brave New World—and then promptly delving into the complicated nature of human horniness certainly makes a provocative first impression. But one of the book’s more surprising arguments is less titillating. The most justifiable use case for biochemical intervention, the authors argue, is to rescue what they call “gray” marriages—unhappy unions that aren’t hateful or abusive, just unsatisfying—between people with kids, and especially those that are at risk of divorce.

According to Earp and Savulescu, unhappily married couples with young kids are the best candidates for biochemical assistance because “when discord is high, divorce appears to benefit children, but when discord is low, divorce appears to harm children.” Children who are harmed by divorce, the authors note, often get “swept under the rug, usually in the rush to defend the right of adults, especially women, to leave bad relationships.”

Earp and Savulescu are careful to differentiate between bad relationships that have simply reached a stagnation point and bad relationships that put one or both parties at risk of real physical or psychological harm; the former, they argue, could perhaps be helped by chemically assisted therapies, while the latter should simply be dissolved. But they go on to assert that “the nuances of children’s welfare in response to different parental choices should not just be waved away.” So for the sake of the children of “gray” marriages, they contend, maybe parents—after all other available therapy and counseling options have been exhausted—could turn to biochemical treatments.

The kinds of treatments Earp and Savulescu mention include oxytocin nasal sprays and MDMA. External boosts of oxytocin—the hormone associated with a number of social, sexual, and reproductive behaviors—has in some research been seen to “result in prosocial, bonding-enhancing outcomes,” the authors point out. It has also been linked to a reduction in anxiety and stress and an increase in empathy. And in a 2008 Swiss study, researchers found that when couples used an oxytocin nasal spray before having a conversation about a persistent source of conflict, the drug “increased the ratio of positive to negative communication behaviors.” So if such a treatment were available in a relationship-therapy context, the logic goes, partners might be able to approach each other with less defensiveness.

The authors make a similar case for MDMA (known in its street-drug form as ecstasy or molly), which, before it was categorized as a Schedule I substance and made illegal for sale or use in the U.S. in 1985, was occasionally administered in a couples-therapy context. Love Drugs documents the case of two psychiatrists who treated about 80 clients with MDMA from 1980 to 1985. (The patients had been prescreened—the psychiatrists didn’t want to work with anyone whose heart was set on being “cured” of a psychological problem through MDMA use—and had consented to the chemical assistance.) In these sessions, a couple would take the drug together, listen to classical music with eye masks on while it kicked in, and then, when they felt ready, talk. Many of the couples, under the psychiatrists’ supervision, would talk for hours, and experienced what they characterized as emotional breakthroughs. The authors attribute that to the way MDMA is understood to “decrease irrational fear responses to perceived emotional threats.” (For much the same reason, MDMA has recently been found to help reduce PTSD symptoms in veterans and first responders.)

Irrational anxieties and emotional repression can of course cause relationship problems, so it’s feasible that a few hours of reduced inhibitions and fears, paired with some gentle guidance from a therapist, might help some couples. The two psychiatrists found that some 90 percent of their clients benefited, and many of them reported that they “felt more love toward their partners and were better able to move beyond past pain and pointless grudges.”

Earp and Savulescu are careful to point out—at several points throughout their book—that drugs like these have shown promise in some settings, but require much more research before they should ever be considered viable mainstream treatment options. And if they ever reach that status, “Such drugs should never be taken in a vacuum, alone or with unprepared others, without the right mental or emotional groundwork, or with the expectation that they will induce improvements all on their own,” the authors write. “They won’t.”

Dominic Sisti, who teaches medical ethics and health policy at the University of Pennsylvania, notes a widely shared view among bioethicists: Certain drugs and pharmaceuticals can and should be used in therapy contexts. MDMA especially “can help reform the bonds that maybe were under stress, or broken through years of challenges or difficulties in a relationship. Or it can provide insight that maybe the relationship is over,” he told me. “Those are things that often take weeks, months, years of therapy to get to, but MDMA sort of catalyzes that.”

Sisti also agreed with Savulescu and Earp’s identification of “gray” marriages with kids as having the most to gain from chemical intervention. Still, he said that some in the bioethics field object to the “love drugs” idea—mainly due to religious or quasi-religious beliefs about love and marriage. “The most common argument [against it] is that you’re sullying something that’s divine,” he said, “that it’s a spark given by God, or preternatural in some way that we shouldn’t be screwing around with.”

Earp and Savulescu acknowledge the criticism, but they ask readers to consider romantic love the same way they might consider another one of life’s (smaller) pleasures: cake. Imagine the way it feels to eat the first bite of a delicious baked good, they write—and then, imagine that you helped bake it. “Does the cake taste any less delicious to you now? Does knowing the recipe, the chemical makeup of the various ingredients, somehow rob your tongue of the flavor it so craves?”

Indeed, the authors suggest that familiarity with something’s inner workings—how all the ingredients affect one another, how adjusting their ratios might help or hurt the end product—not only won’t spoil the magic, but might enhance it. And in the case of a relationship that has produced a family, that knowledge might just save it.

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