Image caption Jasmine has self-poisoned for the last two years

The number of teenagers in the UK who self-harm by poisoning themselves is on the rise. Girls and young women are particularly at risk, according to a study published this week. What drives them to do it?

"It's like my brain has two bits: the happy bit and the bad bit," says 18-year-old Jasmine. "The bad bit keeps pushing until it takes over. You feel like you're losing control of yourself a little bit more and a little bit more. And then it happens.

"There's something in my brain telling me to do it. It's sort of like having a toddler who's demanding things of you constantly. Eventually you just get so tired and the toddler is annoying you so much that you just give in."

Jasmine is one of thousands of teenagers and young women who self-poison - using substances such as alcohol, painkillers and illegal drugs to make themselves sick. Sometimes they have calculated how much they need to feel badly ill without passing out and having to be taken to hospital.

I self-poison because I actually want to feel something physical rather than just mental Ashton, age 20

Jasmine, who is going to university to study English this autumn, was diagnosed with depression when she was 15 and started self-poisoning when she was 16. She has had a difficult relationship with her mother since she was about 10 and was bullied when she started secondary school.

"You would think exams are the worst time," she says, "but self-poisoning doesn't really work like that. I find it's more the normal stress of my everyday life. It happens every few months on average, but more often than that, if there's a particularly difficult time that I'm going through."

The charity Life Signs describes self-injury as "deliberate, non-suicidal behaviour that inflicts physical harm on your body and is aimed at relieving emotional distress". It says people can be driven to doing it because they think the physical symptoms of self-poisoning and other types of self-injury, such as cutting themselves, will be easier to cope with than their emotional pain.

But charities say self harm doesn't actually alleviate suffering, and although self-poisoners don't want to kill themselves, they put themselves at risk of serious injury and death.

What is self-poisoning?

It is a type of self-harm, normally triggered by anxiety or depression

Doctors say people tend to cut themselves as a way of trying to cope with difficulty in their lives, while self-poisoning can happen to those who feel they can no longer cope

If someone deliberately poisons themselves, it does not always mean they are trying to end their life

Ashton, who is 20 years old, says she gets the urge to self-injure three or four times a week. Usually this takes the form of wanting to cut herself, but about once a month she may resort to self-poisoning.

"It started when I was 16," she says. "At the time I had anorexia. The first time I self-poisoned I overdosed and my mum found me." After that, Ashton continued to self-poison using smaller quantities of substances.

"It's hard to explain," she says. "I self-poison because I actually want to feel something physical rather than just mental. It's a lot easier to describe your symptoms when you feel physically sick - you don't have to explain them to people in the same way as feeling bad emotionally. It's something that takes you away from what you're worrying about. You just feel horrible and sick - physical symptoms."

Ashton has started college and then dropped out "three or four times", she says.

Often they see the problem only in physical terms - what the poison's doing to your liver - but you don't think about that side of things when you're self-poisoning Ashton

"I've got a strong sense of what I've missed out on, especially when my friends have gone off to university. I think that's some of what motivates my self-poisoning now.

"I don't have a very good relationship with my mum and I'm not in education or at work at the moment, but I'm top of the list for a housing programme, which means I should get a bit more space soon."

Researchers at the University of Nottingham say there was a 27% increase in known UK cases of teenage self-harm between 1992 and 2012, with 17,862 incidents reported during that 20-year period. Those most at-risk were girls and women from poor backgrounds.

The figures used in the study record cases where people required medical attention. People who self-poisoned but did not end up in hospital would not show up in the statistics.

The government says it is putting £1.4bn ($2bn) into "transforming" mental health support for young people, but Ashton and Jasmine say that in their experience hospital staff struggle to understand self-poisoning.

"You end up having to explain what happened," says Ashton. "Often they see the problem only in physical terms - what the poison's doing to your liver. But you don't think about that side of things when you're self-poisoning."

Jasmine says after a visit to a hospital accident and emergency department she was referred to a psychotherapist "who wasn't very sympathetic".

"She spoke to me like she was telling me off, rather than trying to understand," she says. "These days I've got much better support, but even if you've got a wide support network it can still be a problem that people don't get it."

Jasmine has developed her own ways of coping when she feels the need to self-injure. She keeps sharp objects out of her bedroom and stays away from painkillers.

"I try to protect myself. It doesn't necessarily help but it's something I try to do anyway. A lot of it's trying to be aware that I need to take care of myself. I've got better at controlling myself and making myself aware that the next time I self-poison could be the last time if I go too far."

Overcoming the urge to self-poison can take years. One person who has managed it is 27-year-old Sarah, who is now an NHS doctor. She started self-harming as a teenager, taking an overdose in the toilet at her school and three more times while at university. She continued to self-poison at a lower level afterwards.

I began to realise that learning to love myself again was really important Sarah, doctor

"My mum was an alcoholic and she was often violent towards me," she says. "I also come from a working-class background and I grew up on a council estate, so I often felt that at university I didn't belong."

But Sarah sought help and was given treatment including art psychotherapy. "It was really hard," she says. "Sometimes I came out of the sessions feeling worse because of the stuff we were discussing, but it got better. I began to realise that learning to love myself again was really important."

Sarah, who has scars from cutting herself and suffered some liver damage from self-poisoning, also took up yoga. "I needed to learn to love my body, as well as my mind and yoga helped me with that," she says. "Aspects like learning how to breathe better helped me to relax."

In February Sarah celebrated a full year without self-poisoning. She continues to practise yoga and hopes, in the future, to speak to teenagers about how they can also overcome it. "It's not easy," she says, "but it can be done."

If you have concerns about the issues dealt with in this article, these organisations offer advice and information:

Life Signs

Harmless

Young Minds

Mind

Samaritans

Black and white photographs by Phil Coomes

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