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A 31-year-old member asked:

when should you take an antihistamine?

2 doctor answers7 doctors weighed in
Dr. Alex Martinez
Specializes in Allergy
For allergies: Antihistamines help the most with sneezing, watery drainage, and itching which are often seen with allergies. Older antihistamines (like benadryl) can make people sleepy and should be used with caution; newer antihistamines (like Claritin (loratadine) & allegra) are less likely to be sedating. Because of their drying effect, some doctors recommend avoiding antihistamines during a respiratory infection.
Dr. Paul Carter
A Verified Doctoranswered
A US doctor answeredLearn more
Multiple reasons: Depending on the type of antihistamine used they can be used to treat things such as allergy symptoms, nausea, dizziness, motion sickness, anxiety, itching, and difficulty sleeping.

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Similar questions

A 32-year-old member asked:

What is the average time needed for an antihistamine to begin to work?

2 doctor answers5 doctors weighed in
Dr. Steven Machtinger
Allergy and Immunology 44 years experience
45-90 minutes: Antihistamines taken by mouth begin to work in about an hour but may take longer if you've just eaten. Antihistamine nasal sprays (astepro, patanase) begin to work in 30 minutes. An antihistamine injection, usually diphenhydramine, sometimes given for a severe allergic reaction or anaphylaxis begins to work in a few minutes.
A 34-year-old member asked:

Is it harmful if you take an antihistamine when it is not needed?

1 doctor answer2 doctors weighed in
Dr. Michael Zacharisen
Allergy and Immunology 33 years experience
Probably not: Antihistamines are one of the safest classes of medications and have been available since the 1940s. At usual doses, there is very few side effects and no harm that will come from taking an antihistamine, especially the newer generation ones such as claritin, clarinex, zyrtec, xyzal (levocetirizine) or allegra.
PH
A 21-year-old male asked:

Can i drink chocloate when having symptoms of cold? Could i take antihistamine now? Thanks.

2 doctor answers3 doctors weighed in
Dr. Powlin Manuel
Allergy and Immunology 51 years experience
Yes, you can!: Good morning, yes, you can drink cholate when having symptoms of cold. You can take an antihistamine for relief of congestion. Steam inhalation may help to facilitate drainage as well as eliminating the cold virus faster. Hot drinks, vitamin c, and vitamin d have been found to be helpful by many. Common cold is caused by viruses and there is no effective treatment other than these measures.
Menlo Park, CA
A 26-year-old male asked:

I know it is not recommended to take more than one antihistamine pill per 24 hours, but some only last ~8 hours. Which ones lasts for 24 hrs?

1 doctor answer2 doctors weighed in
Dr. Michael Palumbo
Allergy and Immunology 23 years experience
Xyzal (levocetirizine) and Clarinex: From experience some of the newer antihistamines such as Xyzal (levocetirizine) and Clarinex seem to be effective for longer time periods. Most antihistamines however peak in effectiveness in the first few hours and start to wear off after 12-15 hours.
North Webster, IN
A 63-year-old male asked:

Can I take a antihistamine along with Tussin DM?

1 doctor answer1 doctor weighed in
Dr. Christian Assad
Cardiology 14 years experience
Cough: Yes. Tussin DM is dextromethorphan hydrobromide and guaifenesin. An antihistamine should not be an issue. Just make sure you are taking it for the correct reason. Assume you are having an allergic reaction causing coughing? Cheers C

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Last updated Sep 28, 2016

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