Question 1

Please can i take more than one antihistamine a day as i have severed hay fever ?
i am on one a day cetrizine hydrochloride tablet but not working

Accepted Answer

You can, but better be under doctor's supervision if you need more than one zyrtec tablet a day,. If nasal symptoms are  bothersome,  OTC  steroid nasal spray can help, read the labels carefully and don't exceed recommended dosage and duration,  preceded by saline nasal washes. If not controlled better see your doctor for assessment and possible referral to an allergist, if you have access to one

Question 2

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?

Accepted Answer

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.

Question 3

How many milligrams of antihistamine can a person take at one time?

Accepted Answer

Different antihistamines have different potencies.  10 mg of Zyrtec is equivalent to 180mg of Allegra (fexofenadine).  Mg doseage as in all medicines are drug specific.  In regard to toxic levels, each has it's own known limit.  However too much antihistamine can lead to deadly arrythmias/  Please use the recommended dose.

Question 4

What is the highest dosage of antihistamine that one person can take at one time?

Accepted Answer

Safety of high dose medications is often unknown. Our experience comes from case reports of persons who intentionally or accidentally consumed unusually excessive quantities. When Claritin (loratadine) was first investigated, safety studies were done at 40 mg (4 times the current recommended dose). We take 10 mg because effectiveness is not significantly different between 10 mg and 40mg.

Question 5

Can i take one antihistaminic at moorning and another one at nigt? for alergic reactions.

Accepted Answer

Antihistamines can be taking twice a day safely if required but there are other treatments available. If by allergic reaction you are referring to seasonal allergies, the gold-standard therapy is daily nasal steroid sprays and/or antihistamine nasal sprays. Nasal saline rinses, avoidance measures, and if refractory to treatment, allergy shots can also be helpful. See an Allergist for more details.

Question 6

Hi..i took three antihistamines by mistake when i was told to take only one at night. is this dangerous? each tablet is 120 gms

Accepted Answer

Antihistamines have a high safety margin although the older antihistamines may have more side effects. It is unusual to have mistakenly taken 3 pills when most medication is based on 1 pill. You will have to be more careful in the future since other medications may not be as forgiving.

Question 7

Can i take two claritin (loratadine) antihistamine in one day?

Accepted Answer

Antihistamines are well tolerated even when the dose is doubled.

Question 8

Can an antihistamine like actifed kill you if you take too many at one time?

Accepted Answer

Actifed is more of decongestant. Yes it may harm you.

Question 9

Is it safe to take another 24-hour zyrtec (cetirizine) antihistamine if there's still about 8 hours left before the previous one wears off?

Accepted Answer

You can take another xyrtec but you may become very sleepy.

Question 10

Can you take generic multi symptom night time medicine with night time thera-flu? i don't usually get drowsy from just one dose of antihistamine. i have adhd so it's hard for me to get sleepy from that. so is it okay to take both?

Accepted Answer

Those preparations contain multiple drugs similar to thera-flu, the problem isn't with antihistamines only, other components could interact, or interact with whatever medicines you are on or if you are under treatment for adhd, please consult your doctor and read the labels carefully, good that you asked , always exercise caution with multiple medications,

Can I take more than one antihistamine

Please can i take more than one antihistamine a day as i have severed hay fever ? i am on one a day cetrizine hydrochloride tablet but not working

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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?

How many milligrams of antihistamine can a person take at one time?

What is the highest dosage of antihistamine that one person can take at one time?

Can i take one antihistaminic at moorning and another one at nigt? for alergic reactions.

Hi..i took three antihistamines by mistake when i was told to take only one at night. is this dangerous? each tablet is 120 gms

Can i take two claritin (loratadine) antihistamine in one day?

Can an antihistamine like actifed kill you if you take too many at one time?

Is it safe to take another 24-hour zyrtec (cetirizine) antihistamine if there's still about 8 hours left before the previous one wears off?

Can you take generic multi symptom night time medicine with night time thera-flu? i don't usually get drowsy from just one dose of antihistamine. i have adhd so it's hard for me to get sleepy from that. so is it okay to take both?

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