Hay-fever pills in Alzheimer's link

The Daily Mail reports:

Over-the-counter sleeping aids and hay-fever treatments can increase the risk of Alzheimer's, a study has found.

The sleeping aid Nytol and anti-allergy pills Benadryl and Piriton all belong to a class of medication highlighted in a warning from researchers.

Each of these drugs has "anticholinergic" blocking effects on the nervous system that are said to raise the likelihood of developing Alzheimer's and other forms of dementia significantly at higher doses over several years.

Side effects from these pills?