Samantha asked
I've heard of non-drowsy Benadryl but can't find it anywhere. Is there such a thing? Benadryl works great for me but it does make me tired.
Answer
Benadryl, also known by its generic name diphenhydramine, is
an antihistamine that does commonly cause drowsiness. It is a common misunderstanding that there is a 'non-drowsy' form of Benadryl, but there unfortunately is no such product.
While there are no special formulations of Benadryl that are non-drowsy, there are alternative antihistamines that are less likely to cause drowsiness. Simply put, there is no special formulation of diphenhydramine that won't cause drowsiness.
'Non-drowsy Benadryl' simply refers to an alternative antihistamine that is not diphenhydramine. Depending on what you are using the Benadryl for, you may be able to substitute other over-the-counter antihistamines.
If you are looking for a non-drowsy allergy medication, "second-generation" antihistamines are your best bet. Most are classified as 'non-drowsy' and can last up to 24 hours per dose. "Second-generation" antihistamines include:
- Allegra (fexofenadine)
- Claritin (loratadine)
- Zyrtec (cetirizine)
Allegra and Claritin are considered non-drowsy while Zyrtec has around a 5-15% incidence of drowsiness. It still is far less than the sedation caused by Benadryl.
How Antihistamines Work
Antihistamines work by binding to histamine receptors that are found in the nose, lungs, eyes, and skin without activating the histamine response. By binding and changing the shape of the histamine receptor, antihistamines inhibit histamine from binding.
If and when histamine does bind to their respective receptors, it creates an immune response to essentially attempt to remove the offensive allergen. Histamine can be triggered by a variety of things including pollen, dust, and pet dander. Some people are more sensitive to this response and may not even know what triggers their allergies. Antihistamines are useful in preventing the immune cascade so common in people suffering from allergies.
Antihistamine Medication
Antihistamines are widely used for self-care of allergy symptoms including runny nose, watery eyes, sneezing, and itching of the nose, throat, or eyes.
Benadryl is considered to be a first-generation antihistamine which are generally known to be more sedating than the second-generation class of antihistamines.
Other first generation antihistamines include:
- Dramamine (dimenhydrinate)
- Chlor-Trimeton (chlorpheniramine)
- Tavist (clemastine)
- Meclizine
First-generation antihistamines cross the blood-brain barrier and have CNS effects like drowsiness and
dizziness. First generation antihistamines can also cause urinary
retention, GI upset, and blurry vision. The first generation antihistamines are
also listed as medications to avoid in elderly adults by the Beers Criteria
due to the increased risk of confusion, dry mouth, and drowsiness.
Second generation antihistamines include:
- Allegra (fexofenadine)
- Claritin (loratadine)
- Zyrtec (cetirizine)
Second-generation antihistamines are generally non-sedating, however Zyrtec has been shown to cause at least some drowsiness (as stated above). Other potential side effects of antihistamines include:
- Headache
- Vomiting
- Upset stomach
- Dizziness
Summary
- There is no such product as 'non-drowsy' Benadryl.
- Typically, 'Non-drowsy' Benadryl simply refers to alternative antihistamines (like Claritin and Allegra), that do not cause drowsiness.
