Why did I react to benedryl like this?
Asked by
Mariah (
25883
)
August 7th, 2010
I receive medication at the hospital once every two months, and they give me benedryl beforehand to prevent an allergic reaction. Usually they give me two small pills and it makes me pretty sleepy, but it happens kind of gradually and not to a ridiculous extent. Yesterday, however, I was given one larger pill. When I questioned it they said the dosage of the one pill was equal to that of the two smaller pills I usually receive. But it hit me like a rock! I got very tired, VERY suddenly, felt like all my limbs were extremely heavy and fell asleep even though I was trying not to. Why would this happen if the dosage is the same? Was it released or absorbed differently because it was one pill instead of two?
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4 Answers
My “guess’ is just what you guessed at in that it was not as time released as what you were used to and you may experienced the full on effect all at once from that larger single dose pill! Next time I would ask them to show you the milligrams and also ask for the 2 smaller pills.
Benadryl is a brand name for Diphenhydramine. It’s been around a long time so there are a lot of different generic companies producing it.
The other possibility is that the larger pill was manufactured by a different company which used different binding agents (the filler stuff which contains the active ingredients).
The govt. requirement for generic manufacturers is that medications must contain the exact same amount of the active ingredient.
The choice of filler ingredients are left up to each company. With some meds the filler ingredients can affect bioavailability (the rate at which your body absorbs it into your system).
This is usually only significant with things like heart medications or such where a steady rate of avaiibility is important. This is why sometimes Drs. will specify that it must only be the brand name.
In the case of Benadryl, the sleepiness is a side effect which has nothing to do with the reason they’re giving it to you so it doesn’t really matter that much. The active ingredient (the anti-histamine) is what they care about).
So the binding agents could be different and the larger dose pill gets into your system faster due to its different bioavailibility rate.
I take Benadryl at night so I’ve experienced this. I always take the smaller 25 mg. pills but buy generic. Even tho the amounts are the same and it’s always the smaller pills, the rate at which the sleepiness takes effect varies from one company’s product to another.
Another factor to consider is how recently you have eaten. The emptier your stomach is the sooner you are likely to feel the effects of anything from pills to booze.
This is why they advise people planning on drinking a lot in an evening on the town to eat something containing protein at first so they don’t get so drunk so fast.
Next time try having a few eggs or a hamburger before going to the hospital and see if that might help to slow things down.
Great explanation, @Buttonstc. That answers a lot of questions for me.
It could be that you didn’t have anything in your stomach. It could also be that the two pills were time released when the one pill wasn’t.
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