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How many diphenhydramine should you take at once?

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31 Oct 2012

Hello mike623. Its an antishistamine found in perscription medications as well as over the counter drugs. Sominex, used for sleeping, and Benadryl used for allergies and colds are two examples of the drug. Take as directed if not certain, ask your doctor or pharmacist. Regards pledge

Votes: +1

31 Oct 2012

Diphenhydramine is benadryl & usually comes in 25 mg doses OTC. You can take 2 safely at a time. The max dose for 24 hours is 300mg, but have never heard of anyone taking this much, & definately not all at once. How many you take at one time also depends on others meds you may take also. You don't want to be mixing this with other CNS depressants that will make you sleepy...

Votes: +0
Anonymous 31 Oct 2012

You have a goodday my friend Mary. Be well

Rebelmom16 16 Jan 2014

I see where 300mg is the max dose to take but if I take 250mg will it hurt me, I use them to go to sleep and that's what I have to take

13 Sep 2014

This is bs people saying u can take 300 mg a day!! I take 2 25mg each night for my allergies and to sleep and just called my doc to c if I could take Niquill also because it has the same active ingredient as Benadryl and he said DO NOT DO IT! So at the 50mg I've taken he said anymore would be dangerous!! So ppl get your facts straight cause my info came from a doctor so y'all on here taking random ppls advice better be careful!!!

Votes: +0
dquinonees 23 Nov 2014

When I went to the hospital following an allergic reaction, I was given 100 mgs of benadryl.

EunJi 3 May 2015

First, when they say 300mg they mean over a 24 hour period, not all at once. Second, taking more than 50mg is NOT dangerous. If you do not take it daily you wouldn't want to take more than that. Don't assume that because your doctor told you not to take that much at once that the same applies to others. I have mast cell problems and take between 300mg-500mg on a daily basis (not at once). Now that is after a couple years of taking it, so by no means should someone take that much without discussing it with their doctor. Chances are you won't see this because you posted years ago, but to say it is bs is ignorant. I don't think anyone was implying that 300mg should be taken at one time. By the way, not only do I take that daily, I take a plethora of other medicines with h1 and h2 blockers in it, if I dont I am much more likely to go into anaphylaxis. So just because your doctor told YOU not to take more than that, does NOT mean it is dangerous.

31 Oct 2012

50mg is max one time dose.

Votes: +2

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