Ageing Brains Damaged By Popular Allergy and Antispasmodic Drugs

The risk of chronic disease is steadily increasing worldwide, particularly in the ageing population.

Of particular concern, are neurodegenerative diseases such as dementia which are estimated to affect over a million Australians by 2050, quadrupling from numbers of around 250 000 in 2009.

A recent study has found that in addition to genetic, lifestyle and dietary factors, certain medications may put you in a high risk category for developing cognitive impairment.

Authors of the study published in the Alzheimer’s & Dementia Journal have reported that use of anticholinergic (AC) medications may be a risk factor for developing mild cognitive impairment in older adults.

Drugs with anticholinergic effects are commonly used for conditions such as insomnia, depression, urinary incontinence, cardiovascular problems, behavioral disorders and respiratory conditions, and are available via prescription or in some cases, over-the-counter.

You might recognise some common cold and flu and antihistamine allergy medications such as Dimetapp, Advil and Benadryl – these all contain pharmaceuticals with AC effects.

These drugs block the neurotransmitter, acetylcholine, which is responsible for parasympathetic nervous system control and regulation of memory, concentration, learning, sleep and muscular function.

It is no surprise that AC drugs are associated with the development of cognitive impairment, as acetylcholine deficits are believed a play a major pathophysiological role in the most common form of dementia, Alzheimer’s disease.

The scary thing is – not all of these medications are well known for their anticholinergic effects and may be prescribed for other treatment purposes without proper consideration of a patient’s susceptibility to adverse cognitive effects.


Research Results

This retrospective cohort study included a total of 3690 adults over 65 years of age in primary care clinics throughout Indianapolis.

The research results confirmed that taking strong anticholinergic medications for 60 or more days consecutively caused acute memory problems and increased risk of mild cognitive impairment in patients, compared to non-AC medicated participants.

Similar effects were noted in participants taking 3 or more weaker anticholinergic drugs for a period of 90 or more days.

Anticholinergic medications have also been linked to physical impairment in past studies based on assessments of hand grip, balance and mobility.

At this time, research results do not support a strong association between a diagnosis of dementia and anticholinergic medication use, however this may be due to the relatively short treatment windows assessed in this study.

Previous research does suggest that neurodegenerative changes characteristic of dementia are observed after a minimum of 2 years exposure to AC medications.

Furthermore, it is well known that strong anticholinergics can exacerbate symptoms of pre-existing dementia and should be avoided.


To view a table of Australian drugs with anticholinergic actions based on their potency (Anticholinergic Burden), click on the link below.

 NPS Anticholinergic Medications.pdf


Final Comment

This article highlights again the importance of properly researching any medication you are taking for potential health risks, whether prescribed or over-the-counter, to make informed health decisions.

Medications you might consider to be relatively harmless, especially if self-prescribed and readily available can have dire health effects and taking multiple medications concurrently can be a recipe for disaster.

For more information on supporting cognitive function naturally click here, or connect with a qualified Healthcare practitioner for individualised advice through Emed’s eClinic.


Further Reading:



Bell, S. et al. 2012, Anticholinergic and sedative medicines: Prescribing considerations for people with dementia, Australian Family Physician, Vol. 41(1)

Cai, X. et al. 2012, Long-Term anticholinergic use and the ageing brain, Alzheimer’s & Dementia