One of my first jobs was to keep a lookout for lions. There are some occupations that are not suitable for someone with untreated narcolepsy and this is probably one of them. I was 22, a recent zoology graduate studying meerkats in the Kalahari Desert in South Africa. We worked in pairs, one of us on foot, walking with meerkats, the other in the jeep scanning the horizon for signs of leonine danger. On many occasions, I awoke with the imprint of the steering wheel on my forehead, realising that meerkats and colleague had wandered out of sight. I would look for signs of life and, as the panic grew, signs of death. I can tell this story now only because nobody got eaten.

I have not always been like this. For the first 20 years of my life, I had a healthy relationship with sleep. Shortly after my 21st birthday, though, I began to experience symptoms of narcolepsy, a rare but not-so-rare disorder thought to affect around one in 2,500 people. If people know one thing about narcolepsy, it’s that it involves frequent bouts of uncontrollable sleepiness. This is true, but the condition is so much more disabling, often accompanied by cataplexy (where a strong emotion causes loss of muscle tone and a ragdoll-like collapse), trippy dreams, sleep paralysis, frightening hallucinations and, paradoxically, fractured night-time sleep. There is no cure. Yet.

In the Kalahari, back in 1995, I was new to these symptoms. I had little sense of the incalculable toll that fighting a never-ending battle against sleep (with defeat the inevitable outcome) would take on mind, body and soul. I was not alone. Few family doctors had heard of the disorder, let alone encountered a patient. Some neurologists knew what to look for, but many did not. Not even sleep specialists could explain why this disorder would suddenly strike, with peak onset at around 15 years of age.

A lot has changed in 20 years. There is now overwhelming evidence that by far the most common cause of narcolepsy is an autoimmune attack, where the body’s immune system mishandles an upper respiratory infection and mistakenly wipes out the estimated 30,000 neurons in the centre of the brain.

In an organ of up to 100 billion cells, this might not sound like too much to worry about. But these are no ordinary cells. They are found in the hypothalamus, a small, evolutionarily ancient and unbelievably important structure that helps regulate many of the body’s basic operations, including the daily see-saw between wakefulness and sleep. The cells in question are also the only ones in the brain that express the orexins (also known as hypocretins). This pair of related peptides – short chains of amino acids – were completely unknown at the time of my diagnosis in 1995.

The story of their discovery, beginning in the 1970s, is a brilliant tale of chance and luck, imagination and foresight, risk and rivalry, and involves a colony of narcoleptic Doberman pinschers to boot. It might even be the perfect illustration of how science works.

Yet while there are drugs that can help manage the worst of the symptoms of narcolepsy, none of these comes close to repairing the underlying brain damage. It is remarkable that a lack of two chemicals results in such a bewildering constellation of symptoms. The answer to my problems appears to be simple – I just need to get the orexins (or something similar) back inside my brain. So why am I still waiting?