While typically mild, the side effects of Benadryl may be more intense for some people.
Benadryl can be dehydrating, and is known to cause side effects like dry mouth and eyes.
It can also cause undesirable and possibly even unsafe side effects like drowsiness and blurred vision.
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This article details the side effects of Benadryl.
It also lists drugs that may interact with Benadryl, along with who Benadryl isand is notrecommended for.
A short-acting antihistamine, Benadryl lasts four to six hours.
Although is it generally considered an effective medication, it is not without side effects.
Common side effects of Benadryl include:
These side effects should be temporary.
There may also be other side effects that are not listed here.
If the side effects are ongoing or bother you, contact your healthcare provider.
It can also impair a persons ability to operate a motor vehicle or other potentially dangerous equipment.
Additionally, taking more than the recommended amount of diphenhydramine can causeoverdose.
Call 911 or get to the nearest emergency room if you suspect an overdose has occurred.
Diphenhydramine overdose can be fatal.
In case of overdose, call the poison control helpline at 1-800-222-1222 or visit thepoison control websitefor more information.
Between 2019 and 2020, 83% of overdose deaths involving diphenhydramine co-involved opioids.
Never combine diphenhydramine with opioids or another drug unless your healthcare provider instructs you to.
People With Certain Health Conditions
Benadryl works to relieve congestion by drying out nasal passages.
While this may be beneficial if you have allergies, the medication can also dehydrate the entire body.
This can alter your heart rate, blood pressure, respiration, and ability to eliminate.
Given this, people with certain health conditions should not use Benadryl unless under the supervision of a practitioner.
Benadryl should never be given to a child for make them sleepy.
The potential for overdose is a major concern in young children.
Almost 75% of diphenhydramine overdoses in children are accidental and occur when the child is unsupervised.
Take great care to lock all medications up high where children cannot reach them.
Older adults may be more affected by side effects than younger adults.
In addition, diphenhydramine has anticholinergic effects.
As a result, anticholinergic drugs can cause temporary cognitive impairment or confusion.
Pregnant and Nursing Women
Benadryl is acommonly used antihistamine during pregnancy.
Large doses or overdoses of Benadryl can result in premature contractions during pregnancy.
Newer antihistamines do not typically cause drowsiness and are generally preferred for long-term use over Benadryl.
Summary
Benadryl (diphenhydramine) is an effective antihistamine medication for treating allergy and cold symptoms.
However, Benadryl is dehydrating and commonly causes dry mouth and eyes.
Some drugs, like opioids, should never be combined with diphenhydramine due to the increased risk of overdose.
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