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Is Benadryl Bad for Your Brain?

Jun 22, 2024 | The Healthy Way Newsletter

Benadryl, which is the brand name for diphenhydramine, is commonly used to relieve symptoms of allergies, such as sneezing, runny nose, itching, and watery eyes. It is an antihistamine that works by blocking the action of histamine, a substance in the body that causes allergic symptoms.

Benadryl can also be used to alleviate symptoms of hay fever, allergic reactions to insect bites or stings, and other minor allergic conditions. Additionally, due to its sedating effects, Benadryl is often used as a sleep aid for the short-term relief of occasional sleeplessness. It can help induce drowsiness and promote sleep when taken before bedtime.

Taking any medications may be accompanied by side effects. Today I want to talk in detail about two potential risks associated with brain function while taking Benadryl.

benadryl, allergies, antihistamines, dementia, alzheimer

Risk of dementia in older adults

Diphenhydramine and other first-generation antihistamines are part of a class of drugs called anticholinergics. Some research has linked many anticholinergics to an increased risk of dementia in older people.

One of the first studies to report a link between dementia and anticholinergics, including first-generation antihistamines like Benadryl, was published in 2015.

The results suggest a link between total anticholinergic use and the development of dementia over a 10-year period among people over age 65. According to the authors, there was a link between increased doses of anticholinergics and an increased risk of developing dementia, including Alzheimer’s.

Although they have much in common, dementia and Alzheimer’s disease aren’t the same.

Dementia is not a specific diagnosis. It refers to a broad collection of symptoms that impact daily activities, memory, language, and cognition.

Alzheimer’s is one of several types of dementia. It’s a specific diagnosis associated with certain symptoms and treatments.

Some other studies confirm this discovery, reporting brain atrophy and dysfunction linked to the use of medium or strong anticholinergics. Let’s dive a bit deeper into the nature of this effect.

Anticholinergics are a group of medications that hinder the function of acetylcholine, a neurotransmitter crucial for memory, learning, and cognitive processes in the brain. Certain antihistamines and drugs used for conditions like overactive bladder, depression, and Parkinson’s disease possess anticholinergic properties.

When these medications block acetylcholine receptors in the brain, it diminishes the activity of these neurotransmitters. Acetylcholine plays a vital role in preserving cognitive function and memory, so reducing its activity could potentially impair these functions over time.

Studies have indicated that prolonged use of moderate to strong anticholinergic medications is linked to an elevated risk of developing dementia, including Alzheimer’s disease. The exact mechanism through which anticholinergics might contribute to dementia is not entirely clear, but it is believed that the cumulative effect of blocking acetylcholine receptors over time could result in brain changes that heighten the likelihood of cognitive decline.

benadryl, allergies, antihistamines, drug addiction

Benadryl Addiction

In 2017, Benadryl (diphenhydramine) was listed among the top 10 medications associated with drug-overdose deaths, alongside fentanyl, hydrocodone, cocaine, and heroin.

The half-life of Benadryl (diphenhydramine) in adults ranges from approximately 2.5 to 9 hours, with children typically having a shorter half-life of 3 to 5 hours. In older adults or those with liver issues, the half-life may be longer.

Considering the half-life of Benadryl is crucial when determining dosing frequency, especially if using it for its sedative effects. Taking doses too closely together can lead to an accumulation of the drug in the body, increasing the risk of side effects like drowsiness, dizziness, and impaired coordination.

While Benadryl (diphenhydramine) is not commonly viewed as addictive in the same way as opioids or benzodiazepines, individuals can still develop a psychological dependence or misuse it, particularly for its sedative properties.

Some individuals may misuse Benadryl as a sleep aid or for its sedative effects by taking higher doses than recommended or using it more frequently than directed. This misuse can lead to tolerance, where higher doses are needed for the same effect, as well as psychological dependence, where individuals may feel the need to use Benadryl regularly to fall asleep or manage anxiety. This kind of dependence underscores the compulsive misuse of Benadryl, resulting in increased reliance on the drug for normal functioning, withdrawal symptoms upon cessation, and difficulty in reducing intake.

benadryl, allergies, antihistamines, benadryl misuse

It’s essential to understand that not all anticholinergic medications have the same impact on your health. Some medications exhibit more potent anticholinergic effects than others, underscoring the importance of discussing any concerns regarding potential cognitive side effects with your healthcare provider. If you are taking medications with anticholinergic properties and are apprehensive about their effect on your cognitive well-being, your doctor can assist you in evaluating the risks and benefits and exploring alternative treatment options if necessary.

Your allergy can be treated! Mitigating its symptoms may require a holistic approach, looking into your health history, environment, nutrition, lifestyle, and other components. With this approach, you may notice improvements in your health above and beyond the taming of allergy symptoms.

Take a deeper look into your health and create a plan that supports your well-being while curbing those pesky seasonal allergies. Book a Naturopathic Assessment today!

About Me

I'm Dr. Elena Krasnov, N.D and I've been healing people for decades with my holistic and comprehensive approach to health.

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