The key difference between Zyrtec and Benadryl is that Zyrtec is a second-generation antihistamine that causes fewer side effects, whereas Benadryl is a first-generation antihistamine that causes more side effects.
Antihistamines are medications that are useful in treating symptoms of allergy reactions. Zyrtec and Benadryl are two types of antihistamines. Zyrtec is commonly known as cetirizine.
What is Zyrtec (Cetirizine)?
Zyrtec is a second-generation antihistamine. This medication is important in relieving the worst indoor and outdoor allergy symptoms. This can be found as an over-the-counter product to be used to self-treat. However, it is important to read all the information given in the instructions sheet before using this medication. Moreover, it is available in the form of chewable tablets, rapidly-dissolving tablets, liquid form, etc. When using the chewable tablet, it is important to chew each tablet well and swallow it. When using the rapidly-dissolving tablet, it is important to allow the tablet to dissolve on the tongue and then swallow using water or without water. Moreover, when using the liquid form, it is important to measure the dose carefully using a measuring device.
Allergy reactions due to indoor sources such as dust mites, pet dander, and mold and outdoor allergens such as grass pollen, tree pollen, and mold can be treated using Zyrtec antihistamine medication. The side effects of using Zyrtec include dry mouth, stomach pain (specifically in children), difficulty in urinating, weakness, and some allergic reactions such as rash, itching, swelling, severe dizziness, trouble breathing, etc.
The common name of Zyrtec is cetirizine. The chemical formula of this compound is C21H25ClN2O3. The molar mass of this compound is 388.9 g/mol. It is a member of the class of piperazines in which the hydrogens attached to nitrogen are replaced by a (4-chlorophenyl)(phenyl)methyl and a 2-(carboxymethoxy)ethyl group, respectively. It occurs in the solid state at normal temperature and pressure while appearing as crystals. Its melting point is about 112.5 degrees Celsius while the boiling point is about 542.1 degrees Celsius. It is poorly soluble in water.
What is Benadryl?
Benadryl is a first-generation antihistamine. It is a brand of various antihistamine medications useful in stopping allergies. The composition of this medication can vary from country to country. However, it always contains some combination of diphenhydramine, acrivastine, and cetirizine.
There are different types of Benadryl, including Benadryl allergy, Benadryl allergy relief, Benadryl topical, and Benadryl cough syrup. Benadryl allergy is used in U.S. and Canada. The active ingredient in this product is diphenhydramine. Benadryl allergy relief has acrivastine as the major component. On the other hand, Benadryl topical is a product that comes in topical forms such as gels and creams. It is an itch-stopping cream. Benadryl cough syrup is used in Australia and New Zealand. It comes in the form of cough syrup.
The chemical formula of this compound is C17H21NO. Its molar mass is 255.35 g/mol. The IUPAC name of this compound is 2-benzhydroxy-N,N-dimethylethanamine. Its hydrogen bond donor count is zero, while the hydrogen bond acceptor count is 2. It occurs in a solid state at room temperature and pressure but has an oily appearance. The melting point ranges between 161 – 162 degrees Celsius, and the boiling point is in the range of 150 – 165 degrees Celsius. When considering the stability of the compound, it slowly darkens on exposure to light. But it is stable under ordinary conditions.
What is the Difference Between Zyrtec and Benadryl?
Zyrtec and Benadryl are important types of antihistamines. The key difference between Zyrtec and Benadryl is that Zyrtec is a second-generation antihistamine that causes fewer side effects, whereas Benadryl is a first-generation antihistamine, and it can cause more side effects.
The below infographic presents the differences between Zyrtec and Benadryl in tabular form for side-by-side comparison.
Summary – Zyrtec vs Benadryl
Zyrtec and Benadryl are two types of antihistamines that can treat symptoms of allergies. The key difference between Zyrtec and Benadryl is that Zyrtec is a second-generation antihistamine and causes fewer side effects, whereas Benadryl is a first-generation antihistamine and causes more side effects.
1. “Cetirizine.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine.
1. “Cetirizine Blister Pack” By Brett Jordan (CC BY 2.0) via Flickr
2. “Benadryl Itch Stopping Gel (4600729217)” By The U.S. Food and Drug Administration – Benadryl Itch Stopping Gel (Public Domain) via Commons Wikimedia