Can Antihistamines Cause Alzheimer’s?

“It’s as safe as aspirin.” Was a saying for many years. Now aspirin is known to be quite toxic, causes bleeding, ulcers, and other stomach problems. In fact, where doctors used to recommend an aspirin a day to prevent heart attacks. But now it is known that the aspirin is more dangerous than the heart attack.

How could it happen that we have lived whole lifetimes with something generally considered safe by all and is now found to be dangerous?

Now with more research, those “safe-as-aspirin” medications we have taken like candy for sixty years are found to harm the body. Like all medications, these OTC cold, insomnia, or allergies drugs are toxic.[1] But these specific non-prescription medicines can affect the brain, and may damage it permanently. They are antihistamines and come with many different uses. Antihistamines are used for allergies, but also hide in cold remedies, sleeping pills, and treatment for vertigo.

Antihistamines for Sleep

Jared has struggled with sleeping problems most of his life. He was taking an OTC sleeping pill that he felt was safe because it doesn’t require a prescription. Yet when he brought it to my office, I found out that it contained diphenhydramine, a common allergy medication. Jared is in a terrible conundrum.

• If he doesn’t sleep, his brain doesn’t function during the day.
• On the other hand, if he takes the sleeping agent with diphenhydramine, he has a significant risk of causing permanent brain damage.

Benadryl, or diphenhydramine, has been linked to serious mental complications when used in excess and for long periods of time. Taking diphenhydramine over time can actually predispose people to dementia. The dose and length of time taking these seems to make a difference. Taking diphenhydramine for less than three months has little effect. But using diphenhydramine for over three years shows a 54% increase in risk of Alzheimer’s disease. You should be careful not to use these types of medicines all the time in order to get good sleep.[2]

Diphenhydramine is an antihistamine active ingredient that has a number of different uses in over-the-counter (OTC) medicines, such as:

• Sleep aids
• Sedatives
• Colds and Flu
• Allergy Relief
• Hay Fever
• Dizziness or vertigo
• Motion sickness

More and more studies[3],[4] are indicating that these over-the-counter medications can affect the brain in negative ways, causing:

• Brain fog (cognitive deficits)
• Memory lapses
• Confusion
• Dementia
• Falls
• Automobile accidents

The use of diphenhydramine antihistamine medicine can treat allergy and cold symptoms such as sneezing and watery eyes. But they also block a very important neurotransmitter that controls memory, cognition, and the autonomic nervous system – ACETYLCHOLINE. This is the most abundant neurotransmitter in the body, acting on the brain, the spinal cord, the ganglia of the autonomic nervous system, and all the muscles of your body. The actions of this neurotransmitter include:[5]

• Modulates attention, motivation, and arousal
• Causes muscle contraction
• Regulates movement of the stomach and intestines
• Slows the heart rate
• Relaxes blood vessels
• Increases body secretions

It’s easy to see how blocking acetylcholine can have a lot of effects on the body. Dry mouth, dry eyes, difficulty urinating, constipation, fast heart rate, sedation and spasms are all side-effects of taking antihistamines.

There are many other drugs that block acetylcholine. Dr. Malaz Boustani and her colleagues at the Regenstrief Institute and the Indiana University Center for Aging Research have developed a scale of the effects of various medications on the brain. They are divided into three groups.

• Group 1 are those medications that may have some effect because they have some anticholinergic properties
• Group 2 have a small effect
• Group 3 definitely affects memory and cognition

If you are taking more than one and they add up to 3 or more, it may affect your brain as if you were taking a medication in group 3.[6]

Besides medications, some of the worst toxins also affect acetylcholine.

• Black Widow toxin
• Sarin (nerve gas)
• Organophosphates (pesticides)

Keeping your acetylcholine is essential for your brain and body to function. It is best to avoid all those things that are toxic to this system. This is a good reason to eat organic produce – to avoid eating pesticides. Studies have found significant differences in people who eat organic versus those who don’t.[7]

Also, you should be careful not to use these types of medicines all the time in order to get good sleep.

What to use instead of antihistamines

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