EIGHT MONTHS AGO, Peter, a father of two in his mid-40s, was looking down a black hole. He couldn't function at work or at home - but had no idea what was wrong with him. Sometimes, he'd stand outside his home and wait for his children to go to sleep, afraid of how he might react around them. He was obsessed with irrational thoughts, but couldn't discuss them with anyone. Each day, Peter went through the motions at work, but he wasn't really there. He'd also lock doors and the repeatedly check that he'd locked them. 'I'd spend a large part of my afternoons trying to get something out of my mind,' says Peter (not his real name). 'People would look at me and say, 'Are you with us?' I thought there was some kind of psychological reason for it, that maybe something had happened in my childhood.' Eventually, he couldn't cope any more and sought help from a therapist. After a few sessions, she diagnosed him as suffering from obsessive compulsive disorder (OCD) and prescribed the anti-depressant Seroxat with continued therapy. 'There are still some residual things,' he says. 'But even if it stayed like this and didn't improve more, I'd say my life now is great.' For Peter, who runs his own business in Hong Kong, the first step of getting help was a big one. 'It was really tough,' he says. 'It's admitting that you're ill and there's something really badly wrong. I couldn't say anything for the first hour. I just cried. I discovered that I'd been really badly depressed for much longer than I thought.' OCD and panic and anxiety attacks are a mixed bunch. They all come under the same mental disorder family, but differ in how they manifest themselves. But some things are clear, says clinical psychologist Carolyn Neunuebel. They are chemical problems that are mostly likely to be inherited - and can be treated. A person suffering from general anxiety doesn't have panic attacks but is anxious all the time. This can lead to depression. Then, there are panic attacks, with or without agoraphobia (fear of going outdoors). There are also general phobias, such as social phobia, which is one of the most common conditions Neunuebel sees in Hong Kong. OCD is considered to be an anxiety disorder because of the worrying and the checking, such as Peter's need to keep making sure the door was locked. 'The genetic component has to do with low serotonin,' says Neunuebel. 'Medication can increase that. If someone takes a medicine such as Xanex [for panic attacks], they're only treating the symptoms. Xanex is like an insurance policy.' Serotonin is a neurotransmitter - the molecules by which the brain cells, or neurons, communicate with each other. A lack of serotonin can lead to irrational and obsessive thoughts, depression and repetitive habits, such as excessive hand washing and counting. If you were to do a web search for Seroxat (sold as Paxil in the US), you might get the impression that the drug is bad news. It reportedly can cause violent outbursts and self-abuse, and can be addictive, with severe withdrawal symptoms. 'If I'd know what I'd have to go through, there's no way that I'd have started taking the drug,' a woman by the name of Helen told the BBC in a report called The Secrets of Seroxat. However, thousands of others say the drug has changed their lives for the better and that they'll never come off it - despite one side-effect being a significantly reduced libido. In 2000, GlaxoSmithKline reported sales for Seroxat and Paxil of #348 million ($5 billion) and US$560 million for the first quarter to March 31 - up 24 per cent on the same quarter the previous year. Since then, sales have dipped because of generic brands. However, sales of Seroxat have steadily increased in Japan, for example, since it was approved by the US Federal Drug Administration in 2003 for the treatment of social anxiety disorder. 'I think a lot of what's written is a misunderstanding, especially about the increasing suicidal thoughts,' Neunuebel says. 'It can - but not always - cause an increase in suicidal thoughts in the first two weeks, and the person needs to be monitored by their doctor. People should be warned about this by the doctor. 'Seroxat doesn't suit all people. But in my experience, it's most likely to help them - especially when it comes to OCD.' GlaxoSmithKline's Alastair Benbow has defended the use of the drug, saying that, although he feels sympathy for people suffering from side effects, 'that does have to be balanced by the enormous benefit that's seen by many millions of patients around the world'. For 57-year-old Liz, depression, panic attacks and anxiety have been a part of life since she was in her early 20s. Originally from Britain, Liz (not her real name) has lived in Hong Kong for more than seven years. 'I'm amazed that I came here,' she says. 'There are so many crowds, but it hasn't bothered me at all.' Earlier in her life, Liz says, she would have panic attacks in large malls and crowded shopping centres. 'I was shaky and my head was buzzing. Initially, it felt like you were having a heart attack. But now I know, no matter how bad it is, you're not going to die from a panic attack. It just feels like it at the time. 'I have children and I used to think, well, I'll get them off to school and that's all I have to do and then I can go back home and stay inside. But it's got a lot better through medication and therapy.' People can suffer a panic attack without anyone around them seeing it. 'But to the person who is having it, it feels like everyone can,' says Neunuebel. Liz now knows that she was born with a predisposition to panic attacks. But she says her depression may have been triggered when she was 10 and a close friend was run over by a lorry. Also, her grandmother collapsed in front of her and died. 'I'm not sure which came first [the depression or the panic attacks],' she says. 'But I remember my mother being like this.' Liz sought treatment early, and now has the tools to manage her condition. Her husband has also been supportive. 'At first, he didn't know what to do,' she says. 'It took him a long time to understand. But now he's super.' Liz uses deep-breathing relaxation techniques taught to her by a therapist, she has a music tape she plays if an attack is coming, and has two good friends she can call should an attack feel imminent. She takes anti-depressants with a mood stabiliser, but manages the attacks through meditation, slow breathing or the relaxation music tapes. She also has Xanex in case nothing else works. 'The main thing is seeking help,' she says. 'You don't have to feel that way. It's only a feeling and it will go away, but you have to catch it early.' Neunuebel says that, before drugs such as Seroxat, the only treatment was Valium. But this didn't treat the low serotonin levels and could become addictive. Were such mental disorders as prevalent 15 years ago? 'I think it's just being diagnosed more,' she says. 'It's mostly women who come to see me, but I think that's because men find it more difficult to seek help.'