Hay fever medications increase risk of Alzheimer's and dementia

(NaturalNews) A new study is linking commonly used medicines, which include over-the-counter treatments, of ailments like hay fever and insomnia to dementia and possibly Alzheimer's disease.

According to the BBC, researchers in the study noted that all of the medications examined are drugs that produce an "anticholinergic" effect, meaning drugs that block the neurotransmitter acetylcholine in the central and the peripheral nervous system.

The researchers, from the University of Washington, are recommending that anyone taking such medications (which will be named below) should stop doing so immediately.

The study, published in the U.S. journal JAMA Internal Medicine, found that higher doses of such meds and their prolonged use could lead to higher risks for dementia in older people.

As further reported by the BBC:

The researchers only looked at older people and found the increased risk appeared when people took drugs every day for three years or more.

All medicines can have side-effects and anticholinergic-type drugs that block a neurotransmitter called acetylcholine are no exception.

Hundreds in study were affected

Currently, information leaflets that accompany anticholinergics only warn of the possibility that they could cause dry mouth, reduced attention span and problems with memory recall. However, researchers are recommending that new warnings be issued to contain the potential link to dementia.

Dr. Shelly Gray, primary author of the study, and colleagues tracked the health of 3,434 people aged 65 and older who, at the outset of the study, demonstrated no signs of dementia.

The research team examined medical and pharmacy records of study participants to learn which had been given an anticholinergic, at what dose the medicine was prescribed and how many times per day they were prescribed the drug. The team then compared that data with subsequent dementia diagnoses over the following decade.

The most commonly used anticholinergics were those used to treat depression, antihistamines for common ailments like hay fever, those to assist in sleeping or otherwise to promote drowsiness, and drugs used to treat urinary incontinence. Almost one-fifth of the drugs were purchased over the counter.

Over the course of the study, 797 of the participants developed dementia, the BBC reported.

Britain's Mirror also reported that drugs with anticholinergic effects also block a chemical transmitter that people with Alzheimer's disease don't have.

"This large study adds to some existing evidence linking anticholinergic drugs to a small increased risk of dementia, but the results don't tell us that these drugs cause the condition," Dr. Simon Ridley of Alzheimer's Research UK told the Mirror.

"There have been concerns that regular use by older people of certain medications with anticholinergic effects, such as sleep aids and hay-fever treatments, can increase the risk of dementia in certain circumstances, which this study supports," Dr. Doug Brown, from the UK's Alzheimer's Society, told the BBC.

"More research is needed"

"However, it is still unclear whether this is the case and if so, whether the effects seen are a result of long-term use or several episodes of short-term use," he added. "More robust research is needed to understand what the potential dangers are, and if some drugs are more likely to have this effect than others.

"We would encourage doctors and pharmacists to be aware of this potential link and would advise anyone concerned about this to speak to their GP before stopping any medication," Brown said.

Matthew Speers, who represents the UK trade association for manufacturers of over-the-counter drugs, told the BBC: "Over-the-counter allergy and sleeping aid products are not intended to be used continuously and people are advised to talk to their pharmacist or doctor if they need to use these products long-term.

"There are a range of allergy products on the market which contain a number of different ingredients, many of which were not considered in this study," Speers noted.

Gray said that her study would continue, noting that some of the study participants agreed to an autopsy after their deaths.

"We will look at the brain pathology and see if we can find a biological mechanism that might explain our results," she said.

Sources:

http://www.mirror.co.uk

http://www.bbc.com

http://www.timeslive.co.za

http://science.naturalnews.com