“I take 20 mg Cialis pill and it works as expected but after sexual intercourse I sometimes feel muscle pain in the back and fatigue. I do not know if this is because I work like a stud or it is a side effect. Anyway I am lucky that I gave it a try.”

“It is not fair that everybody knows about Viagra, Levitra worked perfectly for me and moreover it is less expensive and easier to find. I almost have not experienced any side effects, at least those severe to make sex impossible. Works like a charm.”

Infrared technology is used in patients' bedrooms and can monitor their breathing and pulse.

US psychiatrist and neurologist Karl Deisseroth and his German colleagues Peter Hegemann and Georg Nagel have been awarded for their work.

Early recommendations could be issued if evidence highlights patient safety risks, the chair says.

Hugo Flint-Cahan, 34, was fatally attacked by Rolando Torres-Pena, 22, at a mental health trust in east London.