{"id":125451,"date":"2025-05-23T14:15:10","date_gmt":"2025-05-23T14:15:10","guid":{"rendered":"https:\/\/www.europesays.com\/uk\/125451\/"},"modified":"2025-05-23T14:15:10","modified_gmt":"2025-05-23T14:15:10","slug":"antihistamines-and-dementia-risk-doctors-explain-the-connection","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/uk\/125451\/","title":{"rendered":"Antihistamines And Dementia Risk: Doctors Explain The Connection"},"content":{"rendered":"

Over the last couple of years, stress started interrupting my sleep. I found myself having difficulty falling asleep and, even when I did, waking up in the middle of the night. As a freelancer who makes my own schedule, I attempted to fill in the gaps with occasional naps, but it was still a vicious cycle of feeling constantly exhausted during the day, only to not be able to doze off when my head hit the pillow. <\/p>\n

Still, I didn’t think my issues were serious enough to warrant a doctor’s visit (and didn’t want to deal with the hassle of potentially having to find and see a specialist), so I turned to what I thought was the next best option: Unisom, an over-the-counter sleep aid<\/a>. There\u2019s just one problem about taking this sleep shortcut: meds like Unisom, a.k.a. doxylamine succinate\u2014which are found in both OTC sleep aids and allergy meds\u2014are actually pretty bad for your brain health.<\/p>\n

Though most sleep aids and certain allergy med<\/a> labels indicate that they’re not intended for long-term use, they often don\u2019t say why. A close friend who is also a physician clued me into why these OTC options aren’t ideal: Frequent use of antihistamines that fall into the category of first-generation antihistamines has been tied to an increased risk of dementia. In fact, a study published this year in the World Allergy Organization Journal<\/a> suggests people should avoid taking Benadryl, which is a first-gen antihistamine, altogether. (And, BTW, these meds were put on the market all the way back in 1946, before they were required to undergo safety testing, according to research by the the Journal of Allergy and Clinical Immunology<\/a>.) <\/p>\n

This is a serious concern among medical experts, says Pamela Tambini, MD, an internal medicine physician and medical director at Engage Wellness. “People sometimes assume these medications must be harmless because they are sold over the counter, but if you use them too often or for too long, they can mess with your thinking, make you groggy during the day, and possibly lead to long-term problems,” she says.<\/p>\n

So while they might be safe to take every once in a while, here’s why doctors strongly recommend considering other options for sleep or allergies. <\/p>\n

Meet the experts:<\/strong> Pamela Tambini<\/a>, MD, a Palm Beach Gardens, FL-based double board-certified physician in internal and addiction medicine and medical director at Engage Wellness in Acton, MA, Seetha Bhagavatula, MD, a Maryland-based board-certified geriatrician and internal medicine physician at Remo Health<\/a>. <\/p>\n

Here\u2019s why first generation antihistamines are bad for your brain health.<\/p>\n

First, a quick refresher on what antihistamines are exactly. Antihistamines are medications that work primarily to block histamine, a chemical released by the immune system during allergic reactions or infections, says Seetha Bhagavatula, MD, a board-certified geriatrician and internal medicine physician at Remo Health. Histamine is what causes the uncomfortable allergy symptoms you might experience like a runny nose, itchy eyes, or irritated skin. Luckily, \u201cby preventing histamine from binding to its receptors, antihistamines effectively reduce these allergy-related symptoms throughout the body,” says Dr. Bhagavatula.<\/p>\n

They\u2019re an easily available solve for people with mild seasonal allergies, but these meds affect more than just your runny nose. They also make you sleepy (which is why they pop up in OTC sleep medications) and affect many other systems in your body, Dr. Tambini says. “Since histamine also helps keep you awake, blocking it makes you feel sleepy, which is why they\u2019re often used in sleep aids\u2014they sort of sedate you as a side effect,” Dr. Tambini says.<\/p>\n

However, patients with allergic rhinitis (commonly known as “hay fever”) taking first-generation antihistamines face an increased risk of developing dementia, according to a 2024 study in the Journal of Allergy and Clinical Immunology<\/a>. The study also found some risk with second-generation antihistamines, but the risk was far lower. “There might still be a slight risk for cognitive effects,” says dr. Tambini. “However, that risk is very low for most healthy adults taking them occasionally or even seasonally.”<\/p>\n

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That\u2019s because there\u2019s another major system certain antihistamines affect: Your brain. Older antihistamines, known as first-generation antihistamines, such as diphenhydramine (ZzzQuil) and doxylamine (Unisom) cross into the brain and block histamine receptors there, whereas second-generation antihistamines were designed to avoid that, says Dr. Tambini. They specifically target acetylcholine\u2014which happens to be a key brain chemical involved in memory, focus, and learning. This makes an impact on long-term brain health, according to the research. Frequent sleep medication use was associated with an increased risk of dementia in older adults, highlighting that risk may vary by race as well, according to a 2023 study in the Journal of Alzheimer’s Disease<\/a>.<\/p>\n

“If you are constantly dampening that system with these medications, your brain does not function as well,” Dr. Tambini says. “Over time, that can lead to memory issues or even contribute to cognitive decline, particularly if you\u2019re already at risk.”<\/p>\n

In older adults, these medications can also cause confusion or even increase the risk of falling, but the biggest concern is how they impact the brain over time, especially when used frequently, Dr. Tambini says. <\/p>\n

Medications that contain first-generation antihistamines:<\/strong><\/p>\n