I was wondering about this, too, so I checked. Apparently, some migraines are caused by histamines -- makes sense, histamines are vasodilators. I'm going to have to try that next time.
Morphine for headaches ?
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I was wondering about this, too, so I checked. Apparently, some migraines are caused by histamines -- makes sense, histamines are vasodilators. I'm going to have to try that next time.
I've asked our neurologists about this, their answer is basically that they don't know. Other antihistamines don't have as strong as an effect, and giving pepcid/xantac doesn't seem to make the benadryl more effective. There is some thought that since benadryl has some local anesthetic effect that perhaps it is numbing the blood vessels in the brain, however it would be fairly dilute at that point.
Benadryl as a local anesthetic? Did that come from those neurologists?
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Interesting, not sure if I would buy the local anesthetic effect, but hey, if it works, it works.
Probably came from a guy who left one on his tongue too long.
As a possible theory, yes.
We use benadryl diluted down to 1% as a local anesthetic for patients who report an allergy to lidocaine/bupivicaine, it's local anesthetic properties are well established in the literature although it is not as potent as a calcium channel blocker.
Thanks, didn't know that.
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I really doubt that diphenhydramine has any direct effect on the majority of migraines. Its mild serotonergic effects may have some value as an adjunct (that is essentially how the triptans work), but I wouldn't be confident in that. As a local anesthetic, it is probably given in far too small of doses to have any appreciable sodium channel blocking effects on the cranial nerves. Lidocaine is a much more reliable sodium channel blocker and it takes essentially a toxic dose of IV lidocaine to work on migraines. Diphenhydramine's biggest value in this setting is probably as an anxiolytic.
Migraines and cluster headaches are actually etiologically complex and variable. Like most chronic pain syndromes, what works for one person often won't work for another person as well. The most reliable rescue treatments are probably triptans and the D2 antagonists (metoclopramide, prochlorperazine, droperidol, etc.).
Things like ketorolac, diphenhydramine, etc. might work for some people but probably aren't really the most effective choices in general. They just find their way into the "let's throw the kitchen sink at this thing" approach that a lot of clinicians take.
Migraines and cluster headaches are actually etiologically complex and variable. Like most chronic pain syndromes, what works for one person often won't work for another person as well. The most reliable rescue treatments are probably triptans and the D2 antagonists (metoclopramide, prochlorperazine, droperidol, etc.).
Things like ketorolac, diphenhydramine, etc. might work for some people but probably aren't really the most effective choices in general. They just find their way into the "let's throw the kitchen sink at this thing" approach that a lot of clinicians take.
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As a bolus for termination of an acute migraine? Probably work for some people, I don't know. Repeated ketamine infusions are used for severe chronic migraines (and lots of other neurogenic pain syndromes) with good success.
Propofol supposedly works well for migraines. There's a fair amount written about it. I don't think I've ever given it explicitly for that purpose, but a few times I've seen people complaining of migraines sedated for a procedure with propofol, and when they wake up they say their migraine is gone.