I have always had a morbid curiosity about snakes. I was born with a love of animals, especially reptiles, and I began drawing snakes at three years old. I caught my first one when I was five and living in Connecticut: it was a small, non-venomous garter snake. Then I began bringing them home and reading about them. My parents tolerated it, and in 1976, when I was 10, they let me have my first boa constrictor.

Soon afterwards my dad took me to the Miami Serpentarium, where I met a guy called Bill Haast, who milked cobras and rattlesnakes. He was injecting himself with the venom, because he believed his blood could be used to treat snakebite victims; he also seemed to be immune to it and claimed to have never been sick for a day in his life. He ended up living to 100. The memory stuck with me.

I moved to London in 1987 and got a job unpacking tarantulas, cobras and rattlesnakes for a business that supplied animals to zoos and universities. It was my dream job, because I had access to all the snakes I wanted. I started taking venomous snakes home, so I could inject their venom, which my boss didn’t mind.

The first time I milked a snake, I used a green tree viper and injected myself using some 0.5ml syringes from the chemist. It was very scary: there was bruising and swelling all over my arm after I put the tiniest drop of venom into a small incision.

That was 28 years ago, and I’ve been injecting myself ever since, every couple of days. For me, it’s like drinking coffee: it’s an energy boost. I haven’t had a cold or a bout of flu in 13 years. The health benefits of snake venom are still being researched. In the US, they’ve used the properties found in snake venom to try to combat cancer cell growth. French scientists also report they have found a potential painkiller in the venom of the black mamba.

I now own 18 snakes, some venomous, some not, and I milk a rattlesnake and two vipers. It’s a dangerous process, though. After covering the mouth of a shot glass with clingfilm, you have to hold the snake behind its head and move it into a position where it will bite down and squirt its venom into the glass. One slip and it could be sticking its fangs into you. It’s a quick and painless process as far as the snake’s concerned – no different from collecting saliva.

I had one near-death experience eight years ago, when I overdosed: I stupidly injected a cocktail made with venom from my rattlesnake, eyelash viper and green tree viper. I did it as part of a health experiment, but it went horribly wrong. It was a very foolish thing to do. I put the needle into my left wrist, and as soon as the venom went in, I knew it was game over. My hand swelled up like a baseball glove and my arm filled with fluid all the way up to my shoulder.

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When I told the doctors that I had deliberately injected three different deadly snake venoms, they couldn’t believe it. I spent three days in intensive care; they said there was a strong possibility they’d have to cut off my arm. In the end, they didn’t, and I discharged myself.

A week later, they insisted I go back and see them. They took photos of my arm and told me they’d never seen such a recovery. I have no doubt that this was down to all my previous injections. I believe that if I were to be bitten by a venomous snake, my chances of survival would be very strong.

I play tennis every week with a friend who’s a lot younger. About an hour before, I inject cobra and rattlesnake venom and feel like a 23-year-old again. I don’t deny it’s cheating, but when you’re 50, having such energy can feel quite surreal.

I’m currently working with scientists including Professor Brian Lohse from the University of Copenhagen. They’re investigating ways of producing a safer anti-venom, which is usually made by injecting animals, mainly horses, with venom. They’re looking at my antibodies as part of their research.

My body has dealt with venom after years of self-immunisation. Everything for me is about looking at nature: what can kill you can also save you. It’s a fine balance, but for me it’s definitely worth it.

• As told to Yousif Nur.

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