'My psychotic breakdown'

"Back in my early teens I didn’t know cannabis could have any long-term effects on my mental health. I tried it at 15 and thought it was quite a mild drug. Its effects seemed a lot less dramatic than drinking alcohol. Smoking weed just made you giggle and eat lots of chocolate.

"Between 15 and 16, I probably smoked it once a week on a Saturday night at parties. Then a frightening thing happened at my friend’s 16th birthday. I smoked a lot and suddenly I was hallucinating, believing I was sinking into the floor. It was really scary, and I decided then to stop smoking dope.

"It was quite easy to give it up as I was changing groups of friends anyway. I left cannabis behind, or so I thought.

"Then, during my final year at school when I was 18, I started to behave unusually. I was always up early in the morning, and I went through a phase of getting very drunk and going out until very late at night.

"I reached breaking point in the summer after my A-levels. I went on holiday with my family and thought that they were plotting against me. I became tearful and accused them of spying on me. I stayed up all night talking to my teenage cousins. Then I would have breakfast and spend the day sightseeing. I didn’t sleep for days on end.

"Everyone was worried about me. I hit a crisis point when I fainted on the floor of the airport on the way home. I was very confused and scared.

"Over the next 48 hours I got worse, thinking my house was bugged and that everyone was plotting against me. In despair, my mother called an ambulance in the middle of the night. I was sectioned and taken to a secure ward of a mental hospital.

"When I was let out three weeks later, I was told I’d had a psychotic breakdown. The doctors hoped it was a one-off, but since then I’ve been through the cycle of mania and depression several times, and been diagnosed with bipolar disorder.

"Without my antidepressants and mood regulators I’d be unable to live a normal life. Even so, I still experience mania and depression; it’s just a lot more under control.

"When I’m manic I’ve learned to regulate it by eating sensibly, exercising a lot, and taking my prescription drugs. When I feel a depression coming, I go swimming and try to lift my mood by reminding myself that this feeling of sadness and hopelessness won’t last forever.

"I’ll never know if the cannabis contributed to me developing bipolar disorder, but I suspect it could have. If I had my time over again, I wouldn’t touch it. Every time I see reports on the news about cannabis causing psychosis or damaging teenage brains, I wish I’d known that at the time."