Common Prescription Drugs Increase Dementia Risk

common prescription drugs increase dementia risk

Common Prescription Drugs Increase Dementia Risk: Chlor-Trimeton one of the drugs increasing dementia risk

Researchers find that using certain common prescription drugs increase dementia risk. Regularly taking anticholinergic drugs means you are at a higher risk of dementia such as Alzheimer’s disease.

Dementia, losing your wit and cognitive abilities as you age are probably at the top of the list of: “diseases I don’t want”, for many of us. Dementia is getting more common across the world as we live longer and longer. Reaching 85 years of age the risk of dementia is 50%. Many previous news items have touched on both what increases the risk of dementia and which maintenance systems are involved in dementia symptoms. Now new research find another risk factor, taking common anticholinergic drugs.

Common Prescription Drugs Increase Dementia Risk 

The findings of the study are published in the journal JAMA Internal Medicine .

This study used a more controlled method than previous work investigating the causes of dementia. Researchers also had a longer follow-up period (seven years) of participants and used detailed pharmacy records to make their conclusions. This is the first study that shows a dose-response between the amount of a prescription drug used and development of dementia.

“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,” said Shelly Gray, PharmD, MS, the first author of the study.

The study included 3,500 seniors, 65 years or older, participating in the Adult Changes in thought (ACT) study. The participants didn’t have dementia at the start of the study. During the study participants were followed up every two years.

The medications linked to an increased risk of developing dementia included tricyclic antidepressants like doxepin (sinequan), antihistamines like chlororpheniramine (chlor-trimeton) and bladder control drugs like oxybutinin (ditropan). Who names these drugs?

Taking any of these drugs in large enough quantities regularly were found to increase the risk of dementia . Two of these drugs do have newer alternatives that aren’t linked to an increased dementia risk. The two drugs with newer alternatives are the tricyclic antidepressants and the old antihistamine. A newer alternative to tricyclin antidepressants are SSRI (serotonin specific re-uptake inhibitors) and for the antihistamines a new generation of that drug are available, one example being Claritin.

Researchers divided study participants by daily dose of the drugs in question and found that using the drugs at lower doses didn’t cause an increased risk of dementia. In people who used them in higher daily doses researchers saw a definite increase in risk that rose together with the dose. These effects weren’t huge but still significant. The greatest risk-increase was 54% at the highest daily dose of prescription medication.

That some common drugs increase dementia risk is important for your doctor to know when he writes out a new prescription. Especially since there are drug alternatives to many of the ailments these drugs treat. 

If providers need to prescribe a medication with anticholinergic effects because it is the best therapy for their patient,” Dr. Gray said, “they should use the lowest effective dose, monitor the therapy regularly to ensure it’s working, and stop the therapy if it’s ineffective.” Anticholinergic effects happen because some medications block the neurotransmitter called acetylcholine in the brain and body, she explained. That can cause many side effects, including drowsiness, constipation, retaining urine, and dry mouth and eyes.

Image Credit: Ian Sterling via flickr.com, CC BY-NC-ND 2.0