Phenergan v Benadryl, opposite sides of the planet..

[DwayneEMTP]

Hey all,

In the U.S. the guidelines that I was trained on and have been exposed to call for Benadryl for allergic reactions, and Phenergan (Promethazine) for nausea and vomiting.

Though when in Afg working with Aussies, and here in PNG, the combination is reversed.

Is one pairing superior to the other? Why?

[chbare]

While chemically very different, both agents are often classified as first generation antihistamines. Both agents have similar histamine blocking effects. However, I am personally not as comfortable using promethazine because of it's side effects profile. It has also been black boxed in the United States. I have also had the unfortunate experience of seeing people develop rather serious dystonic reactions because of promethazine.

My personal bias is for the use of diphenhydramine. In addition, I grew quite fond of using IV dimenhydrinate for nausea and vomiting when I worked overseas. I believe an oral form exists in the United States called Dramamine.

[croaker260]

I am unaware of phenergan being black boxed, except for the pediatric warning under 6 years of age.

Personally, I believe if you are giving an H1 blocker, you should be giving an H2 blocker as well.

[chbare]

It has a black box warning for paediatric respiratory depression (<2 yo) and one for serious tissue injury.

Edit: Added "one" to differentiate the two warnings.

Edited February 20, 2012 by chbare

[Doczilla]

Both are effective (and relatively safe) treatments for nausea and allergic reactions. The BB on phenergan limits its use in pediatrics by practice. Both can be effective for migraine treatment. Phenergan's tendency to cause QT prolongation is shared by many drugs that would treat the same conditions.

'zilla

[DwayneEMTP]

I'd never heard of it for migraine, but I used it on myself when I used to get them, but only because 12.5mg would completely snow me. Babs would pull my IV, and I'd wake up in the morning feeling fine.

I've also, and this may get me a bashing, used it a lot for pain in patients. In Afg where we only had morphine I'd push 12.5mg prior and very often people wouldn't need narcs. I'm sure that's bad, as I don't think that I've ever had a protocol indicating it for pain, but it seemed to work really well, seemed to give them a decent buzz without losing them beneath it if careful, (For the students: You won't get into 'decent buzz' or 'losing them under it' until way, way advanced learning.) and I don't recall any adverse reactions. Though of course I'm not discounting chbare's reports of distonic reactions, it's just not been my experience.

I guess I'm wondering, if we asked the people that created the U.S. protocols that say Phen = N/V, Ben = Allergy, how would they defend that decision over the reverse? And the same question to the upside down people...

Why need we carry both? It seems that Phenergan (fin- Errrrrrrrrrrr-gin) for the Aussies, doesn't have the pregnancy warnings of Benadryl, and would realistically do both jobs, wouldn't it?

I'm guessing that the question is rhetorical, as the whole world seems to carry them both, I'm just not sure when I would use one that the other would be contraindicated, absolute or relatively?

Dwayne

[Kiwiology]

promethazine is very sedating as its an older H1 blocker unlike newer blockers e.g. loratadine which is non-sedating

man they had me talking to sky elephants and pink dogs and all sorts on that shit

Edited February 20, 2012 by kiwimedic

[chbare]

Promethazine can also potentiate some of the effects of morphine. Dwayne, no hard, fast rule here. As Zilla stated, both agents do a reasonable job. My personal bias is against promethazine due to some bad experiences; however, personal mileage will vary.

[1EMT-P]

As someone who has used both of these medications, let me first start off by saying that they are both good medications. I think each medication has some pros & cons. Personally I like Phenergan for migraines, motion sickness, nausea, sedation, vomiting & with pain medications. If you dilute Phenergan & if you give it slowly in a patent IV or if you give it deep IM it works very well. Many times you can decrease the amount of pain medication given.

[Chief1C]

Up until about two months ago, I took Benadryl on almost a daily basis for sleep. Sometimes, so much that it actually made me itchy, vs taking it away. One morning, whilest brushing my teeth, I noticed my left pupil was significantly larger than the right. My doctor is a complete fucking idiot, can't understand 90% of what he's saying anyway. But he wanted me to be promptly taken away by helicopter to a hospital 90mi away, b/c clearly I had a brain injury that I was unaware of..

Cause. Excessive use of Benadryl.