Painkillers 'are the cause' of millions of headaches

They said some were trapped in a "vicious cycle" of taking pain relief, which then caused even more headaches.
The warning came as part of the National Institute for Health and Clinical Excellence's (NICE) first guidelines for treating headaches. It is also recommending acupuncture in some circumstances.
"Medication overuse headaches" feel the same as other common headaches or migraines.
There is no definitive UK data on the incidence of the condition, but studies in other countries suggest 1-2% of people are affected, while the World Health Organization says  figures closer to 5% have been reported.
While painkillers would be many people's instant response, they could be making sufferers feel even worse.
Prof Martin Underwood, from Warwick Medical School, who led the NICE panel, said: "This can end up getting into a vicious cycle where your headache gets worse, so you take more painkillers, so your headache gets worse and this just becomes worse and worse and worse. It is such an easy thing to prevent."

Source  - BBC