Although difficult to singularly define, love seems to be a main cause of our longevity in the evolutionary rat race. Romantic love is seen as a "primary motivation system - a fundamental human mating drive". Yet, of course, heartbreak is always lurking in the shadow of love, ready to pounce.

Heartbreak, like any adversity, at times can be beneficial: it can lead to "personal growth, self-discovery, and a range of other components of a life well-lived," as the authors of a 2013 paper exploring the science of love put it. At other times it can be downright dangerous, leading people to struggle with depression, stress, domestic abuse and suicidal or delusional thoughts. Yet, as science advances, so does its ability to manipulate the natural mechanisms that underly the human body, including our feelings of love and heartbreak.

Ancient medical cures for a broken heart were creative and widely diverse - according to medical historian Nancy Dzaja, they included everything "from herbal remedies to the prescription of sexual intercourse, to drinking water that had been boiled in the desired person’s underwear". Today, homeopathy is perhaps the only one of these traditional medicines still in use, and despite the lack of any evidence that it works better than a placebo, many organisations (including the NHS) endorse homeopathic remedies for some maladies.

However, modern neuroscience and psychopharmacology are finding ways of "curing" broken hearts that might actually work, and there have been several recent studies which address the possibility of using “anti-love biotechnology” as a treatment for the ill effects of love sickness. Anthropologist Helen Fisher of Rutgers University has researched extensively on what neuroscientists call “psychobiological love”, and has argued that it can be broken into three interconnecting stages: lust, attraction and attachment. Each one has its own chemical cause, and its own possible chemical cure - which in turn comes with their own ethical implications.

Curing lust

Lust is driven by the sex hormones testosterone and oestrogen, and methods of blocking them from acting are already available - for example, antidepressant medications (especially selective serotonin reuptake inhibitors, or SSRIs), androgen (i.e. testosterone) blockers, and oral naltrexone (which is normally prescribed to treat alcohol addiction).

A 2013 study in the American Journal of Bioethics looking at the ethical issues of using drugs to prevent lust found that “libido-reducing effects commonly follow from direct or indirect regulation of testosterone levels”, and that it’s “the most important determinant of sexual desires and actual behaviours, particularly in men”.

However, blocking testosterone has a range of side effects. There's vomiting and depression, but the complete loss of all sexual interest or feeling explains the common name for this what happens when trying to kill off lust: chemical castration.

Curing attraction

This is usually where the honeymoon phase is - where couples are constantly on each other’s mind, count the number of kisses in a text and can’t decide who will hang up the phone.

In the attraction stage a group of neurotransmitters (called “monoamines”), such as serotonin, adrenaline and dopamine are important for regulating mood. And, if it wasn’t already obvious, the attraction stage resembles symptoms of obsessive compulsive disorder.

Anti-depressant drugs that boost serotonin levels can offer relief to OCD sufferers. Donatella Marazziti, a professor in psychiatry at the University of Pisa, compared the brain activity of 20 couples who have been madly in love for less than six months with 20 subjects with OCD. She discovered the serotin levels of new lovers were similar to those found in OCD patients - and suggested that OCD medication could alleviate some of the symptoms of a broken heart.

Curing attachment

Couples would probably explode if they stayed in the attraction phase forever, so eventually it fades and the attachment phase takes over. This is possibly the strongest phase, as it means you’ve passed the test of attraction and can now form a longer-lasting commitment.

Two hormones released by the nervous system are important here: oxytocin and vasopressin. Animal studies have shown how we can manipulate these hormones to sever emotional attachments, including in creatures that famously mate for life like the prairie vole. Larry Young, a professor in psychiatry at Emory University, found that by injecting female voles with a drug directly into the brain that blocked oxytocin or vasopressin they become polygamous. Young said "the mechanisms we’re tapping into in voles may also be responsible for those feelings we have of when we’re with a loved one" in a discussion at the DNA Learning Center. If we were to legally solicit a drug that depletes oxytocin levels it would have the consequences of not only severing romantic love, but all relationships.

So, will anti-love drugs be a thing in the future? Probably - but, to go back to the 2013 study in the American Journal of Bioethics, the idea brings with it challenges to “the importance of autonomy and consent in considering whether (or when) to address instances of ‘perilous love’ through pharamacological means”.

The authors conclude: "The science of love and sexuality is still in its very infancy. However, as our understanding of the biological and neurochemical bases of lust, attraction, and attachment in human relationships continues to grow, so will our power to intervene in those systems - for better or for worse."