MY FRIEND Lottie is 5ft 10in, strikingly attractive and has been described as a cross between Arnold Schwarzenegger and a white Grace Jones. She prefers the comparison to Arnie. She also has a letter from a doctor that says she is either a paranoid schizophrenic or a drug-induced psychotic, he is not sure which.

Back in the good old days, she was no more mad than the rest of us. Sure, she was wild, she could drink vast quantities of Special Brew and remain standing as she was thrown out of pubs, but we had all managed that. But when our bodies had had enough, Lottie's wanted more, and after we had gone our separate ways she had a little bit more LSD as well.

Over a couple of years the grapevine kept me abreast of increasingly weird events in Lottie's chaotic life, but nothing prepared me for her condition when she arrived on my doorstep last October. Displaying all the indications of cartoon madness, she would stare, sometimes for hours, at me, the cats, the ceiling, at imaginary scenes being played out on blank walls. She would giggle like a maniac, turning a malevolent stare or pitying gaze on anyone who dared ask what she was laughing at. She babbled incoherently, unable to finish a sentence.

Mutual friends were contacted and amateur diagnoses formed, ranging from stress to acid flashbacks, but an authoritative medical opinion was needed. We phoned everyone from self-help groups to doctors. As the week wore on Lottie's condition deteriorated rapidly and in desperation we turned to hospitals and social workers.

Unless we could get Lottie to present herself at the local psychiatric unit - unlikely, as she was adamant there was nothing wrong and hostile to our suggestions that there was - very little could be done. Since she was not suicidal and had not, as yet, attacked anyone, she could not be admitted against her will.

At one of many clandestine, emotionally charged get-togethers, we concluded we had three alternatives: convince her to go to hospital, kick her out, or chill out a bit. Maybe if we stopped panicking, Lottie would relax and improve.

We returned that night to find her decked out like a Stepford wife in a blonde, bobbed wig and pinny. 'I'm feeling much better today,' she told us. 'The only thing that's wrong now is that one of the cats is green and the other one's red.' It wasn't exactly reassuring, but it was funny enough to take the edge off things.

Later, however, as more people dropped by, Lottie became distressed, distracted by something none of us could see or hear. She looked for a moment as if she was about to burst into tears, then fled the kitchen for the living-room, where she sat bolt upright, clashing her teeth together and snarling. Later, she told me: 'Everyone had guns. I knew if I made one wrong move everyone would die.' What we were seeing was Lottie fighting for survival. I kept thinking, if this is frightening for us, what is it like for her?

The 'fit' carried on for 20 minutes. Two friends, unsure about what else to do, held her very tight and danced with her. It seemed to calm her, but she now recalls seeing razor blades in their mouths.

We now had no choice but to risk tricking her into coming to hospital with us. Once there, we reasoned, she might accept help. But at the local casualty department Lottie sensed betrayal and strode out of the building. Two of us chased her, while another friend stayed and begged the staff to admit her.

When we caught up with her she was furious, determined to wander off into London. Jogging beside her, we implored her to understand what we were trying to do. Eventually, she stopped in her tracks, kicking a wall hard enough to break every toe. Then she grabbed a friend, Linda, and slammed her against the wall, swinging for me in the process. I thought we were going to get the hiding of our lives. She made us promise never to pull such a stunt again, dropped Linda, and marched off to the car.

Dazed and petrified, we drove home in silence. The hospital could not or would not help. That night we were hostages in our own home, watching Lottie's every move as she watched ours.

To her, she told us later, it was like being in a terrorist movie. While in reality we were playing scrabble and watching telly, she watched grim-faced as guns poured from our noses and ears.

The next day we were able to report to the local social worker that Lottie had fulfilled the criteria to be 'sectioned' under the Mental Health Act. We watched, distraught, as a psychiatrist, a doctor, a social worker, two ambulancemen and two policemen took Lottie away. She went quietly and the last thing she said before she left was, 'This is really stupid, can we not just go to the pub?'

Lottie spent a month in hospital before her appeal to be released was granted. She returned to Scotland and we heard nothing for four months. Having gambled with her friendship we were beginning to think we had lost. Then she called.

She was fine, she said, and when I visited her shortly afterwards I was thrilled to find her living in a clean, pleasant hostel, settled into a routine that included regular visits to her family. She was lucid and communicative, and talked enthusiastically about the future.

She had had one spell back in hospital, she told me, due to splitting headaches - a side-effect of the drug Largactil, which she had been prescribed for when she got 'to the end of my rope'.

I did not know that she was still supposed to be taking the tablets every day. Neither did I know that she was heading for her second breakdown, less scared of that than of the pills.

When she turned up in London again, this time on another friend's doorstep, all the symptoms of her illness were back. This time I seriously doubted whether I had the emotional strength to cope. Fortunately, we were spared the trauma of sectioning Lottie again. When she reached crisis point she hit the hospital like a cyclone and admitted herself.

A month later, now on different medication and anxious to stay in London, Lottie was discharged. Despite telling the hospital and social workers that we could not, and would not, take responsibility for her welfare, their failure to find her accommodation meant that she was sleeping on our floor that night. Not only had she been released with only two days' medication, but she had no release papers, no letter of diagnosis and was broke. She was minus three weeks' benefit to which she was entitled, supposedly being organised by the hospital welfare office.

While a friend camped in the housing department, I drove Lottie back to hospital and insisted she was issued with the necessary papers and medication. The next day she was granted temporary bed and breakfast accommodation and two weeks later moved into a shared house. It is filthy and depressing, but it is hers, and is close to us.

Lottie's battle against mental illness will be long and arduous. With each new crisis we will have to wrestle with a complex and reluctant system so that the weight of responsibility is distributed more evenly. We hope for the best. There is only so long that we will be punished for caring.

Lottie's name has been changed.