As we age, many of us rely on prescription medications to manage various health conditions. While these drugs can be incredibly helpful, a growing body of research suggests that some common medication groups may be associated with a subtle, long-term risk to our cognitive health.
This isn’t about causing alarm—it’s about awareness. Understanding which medications have been studied for potential links to dementia can help you have more informed conversations with your doctor about your treatment plan.
Here are the main groups of medications that research has flagged for a
possible association with cognitive decline.
1. Anticholinergic Drugs
This is the group with the most consistent body of evidence. Anticholinergic medications work by blocking acetylcholine, a chemical messenger in the brain that is essential for learning, memory, and attention.
Common Types
| Drug Class | Examples | Common Uses |
|---|---|---|
| Overactive bladder medications | Oxybutynin, Tolterodine | Urinary urgency, incontinence |
| Antidepressants | Amitriptyline, Paroxetine | Depression, anxiety |
| Antihistamines | Diphenhydramine (Benadryl) | Allergies, sleep aids |
| Parkinson’s medications | Trihexyphenidyl, Benztropine | Tremors, muscle stiffness |
What the Research Shows
A population-based study found that taking any anticholinergic drug was significantly associated with a
higher risk of developing mild cognitive impairment (MCI), though not necessarily dementia . Other large-scale studies have also linked strong anticholinergics to increased dementia risk .
Key takeaway: The risk appears to be dose- and duration-dependent. Long-term use of strong anticholinergics is of greatest concern.
2. Benzodiazepines
Benzodiazepines are widely prescribed for insomnia and anxiety, but their long-term effects on the brain have been a subject of debate.
What the Research Shows
A 2025 case-control study found that any benzodiazepine use was associated with dementia (OR 1.65), with the risk being
higher for long-acting versions (OR 2.81) compared to medium-acting ones (OR 1.57) .
However, the same study noted a crucial nuance: the association for chronic use was only significant within the four years before diagnosis. This suggests that in some cases, the medication may have been prescribed for early symptoms of dementia (like anxiety or sleep issues) rather than causing it—a phenomenon called “reverse causality” .
A separate 2025 meta-analysis concluded that chronic benzodiazepine use was associated with a nonsignificant risk of dementia, suggesting the link is not as strong
