Sleeping Aids, Allergy Medicines Linked to Increased Risk of Alzheimer'sJan 29, 2015
A new study published in the journal JAMA Internal Medicine suggests that over-the-counter sleeping aids and hayfever treatments can increase the risk of Alzheimer's Disease. Researchers say that at higher doses, "anticholinergic" drugs such as the sleeping medication Nytol and the allergy drugs Benadryl and Piriton can heighten someone's chances of developing Alzheimer's and other forms of dementia over several years.
According to The Guardian, anticholinergic drugs block the effects of acetylcholine, an important transmitter chemical in the nervous system. Interfering with acetylcholine activity can lead to drowsiness, blurred vision and poor memory. Acetylcholine deficiency is a known characteristic in people with Alzheimer's disease.
"Older adults should be aware that many medications – including some available without a prescription, such as over-the-counter sleep aids – have strong anticholinergic effects. And they should tell their healthcare providers." said Professor Shelly Gray, lead author and director of the geriatric pharmacy programme at the University of Washington School of Pharmacy, according to The Guardian. "Of course, no one should stop taking any therapy without consulting their healthcare provider. Healthcare providers should regularly review their older patients’ drug regimens – including over-the-counter medications – to look for chances to use fewer anticholinergic medications at lower doses."
Studies done in the past have suggested that anticholinergic drugs may be related to cognitive decline in elderly patients. This study, however, is the first to show a dose response; the risk of dementia increased with greater use of the drugs.
To conduct the study, researchers tracked 3,434 men and women over the age of 65 for seven years and analyzed their use of anticholinergic drugs; Alzheimer's developed in 637 participants and 160 developed other types of dementia. The relative risk of dementia was 54 percent in patients taking the highest doses of anticholinergic drugs compared to those who did not take any. There was an increased risk of 63 percent of Alzheimer's alone. There was an increased risk of dementia among people taking at least 10mg daily of doxepin, 4mg daily of diphenhydramine (Nytol, Benadryl) or 5mg per day of oxybutynin (Ditropan) for more than three years.
"These findings … have public health implications for the education of older adults about potential safety risks because some anticholinergics are available as over-the-counter products." the authors concluded. "Given the devastating consequences of dementia, informing older adults about this potentially modifiable risk would allow them to choose alternative products and collaborate with their health care professionals to minimise overall anticholinergic use."