I spoke yesterday to an MD on an anethesist training program for...

I spoke yesterday to an MD on an anethesist training program for about 2 hours on this topic. 

Short answer is ketamine. Which is not an opioid. 

He quite literally laughed at the suggestion of use of methoxy in a hospital. 

Generally very concerned on the effect of methoxy on kidney & liver function. Effectively stating that it carries a clinically very significant risk with regular use. In his opinion it's emergency use is excessive because the ambo's usually have no idea if the patient has used it before, so are taking a gamble with the persons health. Especially as it is increasingly prescribed for minor indications. 

basically said ketamine is more effective, simple to administer IV & IM, less side effects. No brainer to him. 

I pushed him him and he did concede it has a use in an out of hospital emergency medicine where an injection is likely to cause stress to a patient (e.g a kid with a fear & an moderate injury).