Alphaxalone

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I am just wondering if anyone has tried alphaxalone in mice since it came out in a single drug prep in Alfaxan?

I have a scientist who wishes to use it for a 15 -20 minute non-painful procedure, where effectively all we need is restraint (isoflurane appears to affect the parameters being measured and so we can't use it). My understanding was that alphaxalone isn't good i/p and this paper suggests some adverse responses.

We have access to etomidate as a possible alternative.

We tried a few mixes in a workshop a couple of years ago (in the USA) - what you might expect from the previous experience with saffan - i/v I would expect it to be better, but the problem is the rapid metabolism so high dose needed to get anaesthesia. You could try medetomidine/midazolam/butorphanol (no, I didn’t expect it to work, but it did).

Etomidate alone is a possibility - but check out Colin Green’s paper on Metomidate/Fentanyl as he found etomidate less good. (it's in Lab Animal somewhere, 1970s).

I don't know about mice but etomidate (strictly the excipient, propylene glycol) causes haemolysis and pain on IV injection in sheep and pigs, unless diluted with a benzodiazepine.  Not knowing anything different I wouldn't want it i.p. if I were a mouse, or any other small mammal for that matter.