Benadryl (diphenhydramine) and Zyrtec (cetirizine) are over-the-counter (OTC)antihistaminescommonly used to treatallergy symptoms.
Although similar in their uses, Benadryl and Zyrtec have a few distinct differences.
These two types of antihistamines work differently.
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For example, first-generation antihistamines like Benadryl are more likely to cause drowsiness.
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Zyrtec vs. Benadryl: What Do They Do?
They can also be used to treatchronic urticaria(long-term hives).
Both are available OTC (without a prescription) and as generic products.
When your body encounters an allergen, it releases a chemical calledhistamine.
Histamine triggers symptoms of runny nose and congestion.
Drugs that block the histamine H1 receptor relieve symptoms associated with allergies.
Benadryl, a first-generation antihistamine, has been around since 1946.
However, Zyrtec belongs to a newer class of medications called second-generation antihistamines.
Zyrtec is available in 5 and 10 mg tablets and as a liquid.
Dosing recommendations for Zyrtec include:
Both Benadryl and Zyrtec may be taken with or without food.
Both start working quickly, within 15 to 60 minutes of dosing.
Other side effects are fatigue, dry mouth, sore throat, and dizziness.
Safety
Diphenhydramine is a common active ingredient used in multi-ingredient OTC products for cold and allergy symptoms.
Know how the medication affects you before driving a car or any other activity requiring alertness.
Drinking alcohol can increase the drowsiness triggered by these medications, so avoid alcohol during this time.
Both Zyrtec and Benadryl are effective in reducing allergy symptoms.
Studies show that Zyrtec is as effective as Benadryl in treating allergic reactions to chemotherapy treatmentsand food-induced allergic reactions.
Frequently Asked Questions
Yes, usually.
Both Zyrtec and Benadryl are generally considered safe during pregnancy.
If you are pregnant, talk with your healthcare provider about which medications are OK to take.
Zyrtec is effective for treating minor allergic reactions to chemicals, environmental allergens, foods, and drugs.
It is important to note thatepinephrineremains the primary treatment foranaphylactic reactions, which isnotan ingredient in Zyrtec.
People usually take just one antihistamine at a time.
No data suggest that taking Benadryl and Zyrtec together is more effective than taking one at a time.
Furthermore, there is a risk of increased side effects, especially drowsiness and impaired coordination.
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