Over-the counter hayfever tables, sleeping pills or asthma drugs significantly raise the risk of developing dementia, a study has shown.
Taking a daily dose of pills like Benadryl, Piriton and Nytol, for at least three years, can increase the chance of getting Alzheimer’s disease by more than 60 per cent.
Researchers at the University of Washington said pensioners taking over-the-counter drugs should tell their doctors and stop taking medication immediately if it is not needed.
The drugs are known as ‘anticholinergics’ which work by blocking acetylcholine, a chemical involved in the transmission of electrical impulses between nerve cells. People with Alzheimer’s disease are known to lack acetylcholine and it is feared the pills may exacerbate or trigger the condition.
Other drugs on the risk-list include older antidepressants such as doxepin, and the bladder control treatment Ditropan.
The findings showed that people taking at least 10mg per day of doxepin, 4mg per day of diphenhydramine (Nytol, Benadryl) or 5mg per day of oxybutynin (Ditropan) for more than three years were at an increased risk of developing dementia.
Available substitutes that did not have anticholinergic effects included selective serotonin re-uptake inhibitor (SSRI) antidepressants such as Prozac and newer anti-histamine allergy treatments including loratadine (Claritin).
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. 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.
Source: University of Washington, USA