A young man claims that he has become gay after taking painkillers when he broke his foot in a go-karting accident.
Unemployed Scott Purdy, 23, says he was a heterosexual and enjoyed dating women before he started taking Pregabalin, also known as Lyrica.
But he claims he quickly lost his sexual attraction to women and broke up with his girlfriend of six months when prescribed the drug earlier this year, according to the Daily Mail.
Scott, of Louth, Lincolnshire, says he soon realised that he had developed an attraction to men and had actually turned gay.
He said: "I noticed my libido for women had gone and I was wanting male attention.
"I was with a girlfriend I had been with for around six months.
"I had never been interested in men. When I was younger I was a little bit curious, but a couple of weeks after I started taking it I turned around and said I didn't find her physically attractive anymore.
"She knew I was taking Pregabalin.
"I said to her, 'I don't really know what's happening to me and I told her I like men and I just can't be with you.
"She was relatively understanding, as understanding as you could possibly be."
Pregabalin or Lyrica is a medication used to treat epilepsy, pain associated with the brain, and generalised anxiety disorder.
Its documented side effects include loss of libido and mood swings.
Scott, who was prescribed the drug by doctors to treat his pain after he broke his foot in a go-karting accident, added: "I just think people should know about this.
"If anyone gets prescribed this in the future, I think they should know what this medication can do.
"It took me a while to realise what it was. I stopped taking it for a few weeks and that desire for men just left.
"But I'm on it now; I'm very happy. I want to keep on taking it because it makes me feel happy about my sexuality. It's made me feel very open. It's liberating.
"Pregabalin is also used to control paranoia and anxiety. It's made me so open and not bothered what people think or say.
"I had been taking it for a few weeks and I have come to the realisation that when I take it I want males.
"It did come as a shock to people. I posted it on Facebook. I didn't tell them the reason why but I just said to them, 'I'm open; I'm gay.'
"Currently I'm talking to this lad on Plenty of Fish and in a couple of weeks I'm going up to see him. He's in London.
"It's really what I'm craving right now. I want to be with him right now."
Scott had been taking Codeine until January this year, but has been experiencing negative side effects, so his GP prescribed him Pregabalin.
He says that it was only after taking Pregabalin that his sexual preferences changed.
He said: "I feel if this has happened to other people and I'm not the only one I would be outraged but in a sense not be because if I had known this was a side effect before I would not have taken them but now I'm happy.
"I'm not angry because it's made me who I am."
Lyrica is manufactured by Pfizer - the pharmaceutical giant which also makes Viagra used to treat sexual dysfunction in men.
A spokesman for Pfizer said: "When prescribed and administered appropriately as per the approved label, Lyrica (pregabalin) is an important and effective treatment option for many people living with chronic neuropathic pain, generalised anxiety disorder and epilepsy.
"The clinical effectiveness of this medicine has been demonstrated in a large number of robust clinical trials among thousands of patients living with these conditions.
"To date, the worldwide exposure to pregabalin is an estimated 34 million patient years.
"If you are taking a medicine and experience any unexpected side effects, we recommend that you immediately report these to your doctor or to another healthcare professional, such as a nurse or carer.
"The Medicines and Healthcare Products Regulatory Agency (MHRA) can also be contacted through its Yellow Card reporting system
"Patient safety is, and will always be, Pfizer's utmost priority.
"We work with regulatory authorities around the world to continuously evaluate and monitor safety for each and every Pfizer medicine through ongoing clinical research, analysis and surveillance."