Antihistamines and Alzheimer’s: What can we do to reduce the risk?

Dr. Diana Driscoll, Optometrist

Dr. Diana Driscoll, Optometrist


Acetylcholine is the neurotransmitter used by the brain for cognition and short-term memory. Boosting acetylcholine levels is an effective (and FDA-approved) method of treating dementia/Alzheimer’s. We must have optimal levels of acetylcholine to maximize our brain health.

Some of us need antihistamines and may need them chronically. Those of us with allergies, asthma, high IgE levels, mast cell activation syndrome (MCAS), and other chronic inflammatory conditions can improve our symptoms with antihistamines. Some of us cannot achieve the same response through dietary changes.

Even more importantly, histamine has been shown to actually cause Alzheimer’s-like effects on the brain — so it must be controlled!

Is it possible to take antihistamines to block histamine, yet still boost our levels of acetylcholine? After all, antihistamines are taken to block histamine — the anticholinergic effects are a side-effect only (not the mechanism of action of the drug).

As a Patient

As a patient, antihistamines can be hugely helpful for me, but I didn’t want them to affect my brain. For years, I suffered from extreme mental decline due to low acetylcholine levels. Neurological tests showed my short-term memory was almost non-existent. I suffered from such mental fatigue that I have difficulty making a “to-do” list of even 3 items. If I accomplished that feat, then I was too exhausted to do any of the items on the list, and instead, I went back to bed for most of the day.

My case was a dramatic one – at one point I was only able to stay awake for about three hours a day and during those 3 hours, I wanted to be asleep. Even more frightening I felt that I was getting worse every day. Although my problems were not all due to low acetylcholine from antihistamines, I didn’t want the medication to worsen it! Boosting my acetylcholine was the essential missing piece in restoring my cognition and levels of mental energy. This allowed me to stay on necessary antihistamines, yet restore and retain my cognition.

Having lost my mental function for so long, I have no intention of losing it again. I fight both histamine and inflammation by supporting my acetylcholine levels. This is an essential part of my morning — every morning.


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Diana Driscoll, OD

Diana Driscoll, OD

Founder, Clinical Director at POTS Care

Dr. Diana Driscoll, optometrist is a foremost authority on autonomic dysfunction, Postural Orthostatic Tachycardia Syndrome (POTS), Chronic Fatigue Syndrome (ME/CFS), chronic dry eye, vagus nerve disorders Read more...


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