Dementia risk linked to some medicinesA study links the long-term use of some drugs with a higher risk of dementia. The study found no risk with other anticholinergic medicines used to treat common conditions such as hay fever, travel sickness and stomach cramps. It also analysed more than 27 million prescriptions - making it the biggest study of its kind into the long-term impact of anticholinergic drugs in relation to dementia. Not taking prescribed drugs could have serious consequences, Dr Maidment said. Dementia Research national director Prof Martin Rossor said: "It is important to be cautious about associations as they do not prove causation."