My fentanyl experiences have entirely been as part of surgery: it's part of the balanced triad of anaesthesia and I "recently" injured myself quite badly, resulting in three operations. After one of these, I spent about 36 hours on a fentanyl infusion and more than a month on oral morphine of various doses with my leg in an orthopaedic brace while I was bed-bound. I should point out that the alternative was a lot of screaming: visceral pain of the variety I cannot describe – I had a panicked, "help me" expression on my face and just felt utterly, utterly desperate. I was in a lot of pain and medically the drugs were appropriate, given the injuries I sustained.

I totally get why some people become addicted to drugs. Diazepam made me both in less pain and care less that I was in it. The opiates produced this warm, fuzzy haze of vivid dreams and imaginations and made a difficult time bearable. Fentanyl made me feel less than human but not able to suffer, and it was a necessity at the time.

Of all of them though, diazepam was the most dangerous. It just felt – well, nice. I didn't care that things were bad. I needed it medically to stop neurogenic muscle spasms and it made me both able to sleep well and feel OK about life in a way that is really hard to put into words. I have some in a bag, prescribed for me, in case I need it. Part of me – a small part of me, but a part nonetheless – wants to use it, a lot, when I don't need it. There's a little voice that just says "this makes you feel like you've been tucked up into bed nicely". I really can't explain it, but I know that voice is a temptation and a gateway to something that I don't want to have – but at the same time, I know that that drug both saves me from agony and helps me medically if I need it. I'm really not sure how I feel about that. I haven't had any in months, but the psychological aspect remains.

I can only imagine what "real" drug addicts go through. It must be incredibly hard, and individual's range of experiences will be very broad indeed.