Do Allergy Medications Increase Your Alzheimer’s Risk?

I love this time of year. But many of my patients dread springtime…

They come to my clinic sneezing and sniffling. They have runny noses, and watery, itchy eyes. They can’t sleep or work.

You may have the same problems. You need relief fast to get back to your life. So you might be tempted to pop some OTC remedies or ask your doctor for a prescription.

But you may be getting more than you bargained for with those allergy drugs. They may make you lose your mind. Let me explain…

Many doctors treat allergies with a class of drugs called anticholinergics (ACs). You know them by names like Benadryl and Dimetapp.

In a new study, scientists linked ACs to an increased risk of dementia.1

Researchers at the Indiana University School of Medicine looked at 451 people, with an average age of 73. Sixty of the patients were taking at least one AC drug.

They gave the whole group memory and cognitive tests. They did PET scans to measure brain activity. They did MRI scans to measure changes in brain structure.

The results were worrying…

The people taking AC drugs did worse on short-term memory tests. They had worse verbal reasoning, planning skills, and problem-solving.

They also had lower levels of brain activity, especially in the hippocampus — the region of the brain linked with memory. And they had reduced brain volume and larger cavities or holes inside their brains.

In other words, people taking the drugs had more brain atrophy.

And AC drugs cause damage quickly. In fact, using these drugs for as few as 60 or 90 days can cause cognitive problems.2

Allergies are your immune system overreacting to normal dust, pollen, and animal fur. Special cells in the blood vessel linings of the inner eyelids, nasal membranes

, and lungs release substances called histamine and inflammatory prostaglandins. These are the real culprits behind all the misery. They release fluids to flush out what your body thinks is a viral or bacterial infection.

I don’t prescribe those dangerous AC drugs for allergies. Instead, I help my patients relieve the symptoms naturally.

5 Safe, Natural Allergy Busters You Can Use Today

  1. Nasal irrigation. This therapy is a safe and easy way to rinse your sinuses. It flushes allergens and irritants out your nasal passages. You can find nasal rinse applicators, including neti pots and sinus-rinse kits, in most drug stores. Just follow the directions on the box. But one caution… Make sure the water is distilled and as sterile as possible. Tap water isn’t safe because it’s not adequately filtered or treated. And it can increase your risk of infection.
  2. Pineapple. This tropical fruit contains an enzyme called bromelain. It counteracts the effects of inflammatory prostaglandins. To help lessen inflammation, you’ll need to eat about a cup of fresh pineapple every day.

    You can also take a supplement. Look for a capsule that is at or near 2,400 GDU (gelatin dissolving units), the highest standardized potency you can get. I recommend you take 500 mg twice a day.

  3. Quercetin. This bioflavonoid targets the special cells that make histamine. Studies show it prevents allergies before they start. It can even stop allergic reactions in progress. And it works instantly.3

    Quercetin is found naturally in many fruits and vegetables. Try eating more apples, broccoli, cherries, citrus fruit, cranberries, green tea, leafy greens, raspberries, red grapes, onions, shallots, and tomatoes. If you’re prone to allergies, start eating more of these foods a few weeks before spring arrives. Or you can supplement. I recommend taking 500 mg twice a day.

  4. Stinging nettle (urtica dioica). This prickly herb is a natural anti-inflammatory. It can prevent hay fever symptoms if taken as soon as they appear.4 It works by balancing histamine levels and preventing the production of prostaglandins.

    I recommend drinking nettle tea. You can find dried leaves or tea bags in your local health food store or online. Drink one or two cups a day with a meal.

  5. Vitamin C. You already know vitamin C boosts the immune system. But it also halts the production of histamine. And it speeds up the breakdown of histamine already in the blood. One study showed that taking 2,000 mg of vitamin C per day lowered histamine levels by 38% in healthy adults — after just one week.5

To Your Good Health,

Al Sears, MD, CNS


1. Risacher S, et al. “Association between anticholinergic medication use and cognition, brain metabolism, and brain atrophy in cognitively normal older adults.” JAMA Neurol. 2016;73(6):721-32.
2. Xueya C, et al. “Long-term anticholinergic use and the aging brain.” Alzheimers Dement. 2013;9: 377–385.
3. Middleton, E. et al ” Quercetin: an inhibitor of antigen-induced human basophil histamine release.” J Immunol. 1991;127:546-50.
4. Roschek B Jr, et al. “Nettle extract (Urtica dioica) affects key receptors and enzymes associated with allergic rhinitis.” Phytother Res. 2009;23(7):920-6.
5. Johnston, C. et al ” Antihistamine effect of supplemental ascorbic acid and neutrophil chemotaxis.” J Am Coll Nutr. 1992. II(2):172-76