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A 37-year-old member asked:

can you tell me if it's dangerous to take 2 pills of antihistamine (cetirizine) at once?

1 doctor answer1 doctor weighed in
Dr. Michael Rupp
Allergy and Immunology 21 years experience
Maybe: You should not do this without the supervision of a doctor.

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Similar questions

A 44-year-old member asked:

When do I need to take and oral antihistamine for itching as opposed to a topical cream?

2 doctor answers6 doctors weighed in
Dr. Sheila Goodman
Specializes in Obstetrics and Gynecology
If cream not working: The time to switch from a cream to an oral antihistamine is if the itching/rash is widespread enough that you're needing to use a lot of cream or if the cream isn't working. You can certainly combine the cream and the pills. If you develop the symptoms during pregnancy or they don't get better with treatment, talk to your doctor. Rashes during pregnancy can be a sign of complications.
A 26-year-old member asked:

What are allegra and xyzal (levocetirizine) used for?

2 doctor answers5 doctors weighed in
Dr. Stephen Kimura
Allergy and Immunology 35 years experience
Allergies: Allegra and xyzal are two different types of antihistamines. They are called non sedating antihistamines as older antihistamines like Benadryl (diphenhydramine) cause drowsiness in some people. The entire class of medicines are used to treat allergies or allergic reactions.
A 34-year-old member asked:

Why does drowsiness occur after taking antihistamines?

2 doctor answers3 doctors weighed in
Dr. Patrick Melder
ENT and Head and Neck Surgery 27 years experience
Complex: Histamine is a wake promoting neurotransmitter in the brain. Older antihistamines like Benadryl (diphenhydramine) cross into the brain and block this center allowing for drowsiness to occur. The newer antihistamines like alleges, claritin, zyrtec do not cross as easily and are less likely to promote drowsiness.
A 44-year-old member asked:

What happens if you use an ophthalmic antihistamine when you don't have allergic conjunctivitis at the moment?

2 doctor answers3 doctors weighed in
Dr. David Kira
Ophthalmology 21 years experience
May help: Topical antihistamine drops sometime may be prophylactic - especially in the midst of allergy season. We have quite a few known allergic conjunctivitis sufferers start daily drops at the beginning of allergy season and use them throughout.
NV
A 37-year-old member asked:

Is it safe to take two zyrtec (cetirizine) a day, one in the morning and one at night?

2 doctor answers2 doctors weighed in
Dr. Thomas Byrnes
Family Medicine 29 years experience
Sedation: That dose of zyrtec is going to be very sedating. This defeats the purpose of taking zyrtec instead of benadryl (diphenhydramine). That level of sedation will make you a drowsy --> dangerous driver. Have you tried Loratadine or allegra? Do you use Flonase or something like it? Do you regularly flush your nose with a saline/ baking soda solution?

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Last updated Mar 26, 2019
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