Does choline supplementation prevent dementia in patients taking Benadryl (diphenhydramine)?

Choline Supplementation Does Not Prevent Dementia in Patients Taking Benadryl

There is no evidence supporting the use of choline supplementation to prevent dementia in patients taking diphenhydramine (Benadryl). Based on current clinical guidelines, choline supplementation is not recommended for prevention or correction of cognitive decline in persons with or at risk for dementia 1.

Understanding the Relationship Between Diphenhydramine, Cholinergic System, and Dementia

Diphenhydramine (Benadryl) is an anticholinergic medication that blocks acetylcholine receptors in the brain. This mechanism has several implications:

• Anticholinergic medications like diphenhydramine are known to potentially cause cognitive impairment, especially in elderly patients
• The cholinergic system is important for brain function, with acetylcholine being a key neurotransmitter involved in memory and cognition
• Patients with dementia, particularly Alzheimer's disease, often have deficits in cholinergic neurons and reduced choline acetyltransferase activity 2, 3

Evidence on Choline and Dementia Prevention

While the theoretical basis for choline supplementation might seem logical, clinical evidence does not support its use:

• The ESPEN guidelines on nutrition in dementia explicitly state that nutritional supplements, including those containing choline compounds, are not recommended for prevention or correction of cognitive impairment 1
• A recent multicenter study found that choline alfoscerate (a choline precursor) was not associated with reduced progression from mild cognitive impairment to dementia 4
• Although one Framingham Heart Study found that low dietary choline intake was associated with increased risk of incident dementia 5, this does not translate to evidence that supplementation prevents dementia in those taking anticholinergics

Anticholinergic Medications and Dementia Risk

Rather than focusing on choline supplementation, clinical practice should address the underlying issue:

• Anticholinergic medications like diphenhydramine should be used with caution in elderly patients and those at risk for dementia
• The 5th Canadian Consensus Conference on the Diagnosis and Treatment of Dementia recommends deprescribing medications that may worsen cognitive function 1
• Consider alternatives to diphenhydramine when possible, especially for long-term use in older adults

Nutritional Considerations in Dementia

For patients with dementia or at risk of dementia:

• Regular nutritional screening and assessment is recommended 6
• A balanced dietary pattern providing adequate amounts of all essential nutrients is preferred over specific supplementation 1
• In cases of specific nutrient deficiencies (including B12 deficiency), the respective nutrients should be supplemented, but this is different from using supplements to prevent dementia 6

Conclusion

The evidence does not support using choline supplementation to prevent dementia in patients taking diphenhydramine. Instead, clinicians should:

1. Consider alternatives to anticholinergic medications when possible
2. Ensure adequate nutritional intake through diet rather than supplements
3. Reserve nutritional supplementation for cases of documented deficiency
4. Focus on established dementia risk reduction strategies rather than unproven supplements

When anticholinergic medications like diphenhydramine must be used, minimize the dose and duration of treatment to reduce potential cognitive effects.