Why love is addictive.

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Love makes us joyful, obsessive and sometimes sick. And addictive drugs do the same. But why is love such a powerful addiction?

Love and addictive drugs have the same progression: The initial, euphoric, honeymoon period; a drawn-out stage of constant usage, gradually building up a tolerance; and finally a break-up and going cold-turkey. But why would your brain treat your lover like a line of cocaine?

Your brain has a system for rewarding you for the good things that you do. It’s a network of areas of your simpler midbrain and your more complicated frontal lobes. The reward system communicates via the chemical dopamine – dopamine is released to signal to the rest of the brain that something good has happened. Drugs hijack dopamine – they turbocharge the feeling of reward, but when they wear off, you’re left craving another dopamine hit.

That’s the basis of addiction. And each drug drives the reward system in a different way, either directly, or via release of chemicals like serotonin, oxytocin or opioids. But love hits all those pathways… at the same time.

Social contact, physical intimacy and the promise of sex all directly stimulate increased dopamine.

Looking into each other’s eyes, hugging and orgasm release oxytocin from the hypothalamus, which indirectly stimulates the reward system – and it makes those rewarding feelings specific to the one, special person.

Love also releases serotonin and on top of that: opioids! The active ingredient in heroin!

It’s a perfect storm. So no wonder that when you finally fall out of love, and all those chemicals stop coursing round your body, the comedown can be hard. And to make matters worse, now is when your brain starts releasing stress hormone that can make you sick, and make you crave what you’ve lost.

But there is a silver lining. Oxytocin – the same chemical that supersized the love storm – is around to help. Oxytocin is also released during social contact with friends and people you care for – and it lessens the strength of the come-down. And that’s why support from your friends, and other groups has been shown to help recovering addicts - and maybe broken-hearted exes.