The side effects of combining Benadryl and alcohol can be severe.

Benadryl, also known as diphenhydramine, is a medicine available over-the-counter (OTC) that’s frequently used to treat various symptoms related to allergies. People frequently wonder if there are potential side effects or adverse outcomes that can stem from the combination of alcohol and diphenhydramine.

The following provides an overview of the possible side effects of using alcohol and diphenhydramine simultaneously and answers questions like “can alcohol and Benadryl kill you?” 

Side Effects of Mixing Alcohol and Diphenhydramine

The side effects of diphenhydramine and alcohol can be severe, mostly because both affect the central nervous system and depress its functionality. When the central nervous system is depressed, it means that essential functions like respiration also slow down. If you pair alcohol and diphenhydramine together,  it can cause extreme sedation on the central nervous system.

Extreme Sedation

For some, the level of sedation when combining alcohol and diphenhydramine can be so significant that they lose consciousness. Because of this, you should never combine alcohol and diphenhydramine and then drive, operate machinery or plan to be in any potentially risky or unfamiliar situation.


In some people, an overdose is possible with alcohol and diphenhydramine. This could require emergency treatment and hospitalization.

Risks for Seniors

The risks and side effects of alcohol and diphenhydramine can be even more intense for seniors. It can cause problems with their motor skills because of sedation and dizziness, and it can lead to increased risk of falls.

Along with drinking alcohol with diphenhydramine, it’s important that you’re aware of the alcohol content of other medicines you might be taking. For example, some medicines, such as cough syrup, can have up to 10% alcohol content. These may also cause an adverse reaction when paired with Benadryl.

Normal Side Effects of Benadryl 

Some of the side effects of diphenhydramine include drowsiness, dry mouth, headache or urination problems. For some people, the level of drowsiness they experience may be significant. Benadryl may rarely cause some to feel the opposite effect of excitability, but this is more common in children. It’s important, even when you’re not combining alcohol and diphenhydramine, that you don’t drive or operate machinery, particularly if you don’t know how you’ll react to diphenhydramine.

Even in a best-case scenario when you combine alcohol and diphenhydramine, the effects of both are going to be heightened.

Overdose Risk

The answer is yes, although you would likely have to ingest large doses of both. If you overdose on alcohol and diphenhydramine and lose consciousness, death is one of the risks. Despite the fact that it’s commonly used and easily available over the counter, Benadryl can cause dangerous side effects. That’s why you should never mix it with alcohol.

Summing Up…

It’s very important to speak with a physician about your use of alcohol and diphenhydramine. It’s also vital that you never try to combine alcohol and diphenhydramine as a way to help you fall asleep or feel more intoxicated.

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Editor – Nicole LaNeve
Nicole leads a team of passionate, experienced writers, editors and other contributors to create and share accurate, trustworthy information about drug and alcohol addiction, treatment and recovery for The Recovery Village and all Advanced Recovery Systems sites. Read more
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Medically Reviewed By – Dr. Conor Sheehy, PharmD, BCPS, CACP
Dr. Sheehy completed his BS in Molecular Biology at the University of Idaho and went on to complete his Doctor of Pharmacy (PharmD) at the University of Washington in Seattle. Read more
Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.