Are there drugs that would act like endorphins, without being opioid-like (so limited painkilling effect, no addictiveness, no “high”) and if not is it plausible that they could be created?
The purpose would be anti-depressant.
Search the Internet using these terms: “Neurontin” and “antidepressant”. There is a lot of info on it.
Neurontin* is the brand name for Pfizer’s gabapentin. It started out as a pain med to treat “postherpetic neuropathy”, a fancy term for the pain caused by shingles. For pain-management, some people use gabapentin as the primary analgesic, others, as an adjunct to another pain med they’re taking. Some folks found it to be an effective anti-depressant/mood stabilizer. IIRC, one can’t get “high” on gabapentin, but one’s MMV.
Neurontin’s off-label usage has been plagued by controversy, because at one time, Pfizer touted Neurontin as a near-panacea.
Some random musings, and I hope you find them useful.
*Neurontin went generic some years ago.
It doesn’t have anywhere near the abuse potential of opiates, but it can cause euphoria. Erowid has a bunch of reports of getting “high” on gabapentin.
I’ve looked that stuff up, I don’t really see how it’s similar to opioids in any way at all.
To elaborate on this question a bit more, I know of people who essentially self-medicate depression with opioids - not a good idea for a billion reasons - it seems to me in principle that a drug that was like opioids in the way they help with depression, which I understand to be to do with endorphins, but very much unlike them in other ways, would be a wonder drug - if such a drug is possible, at least in theory.
Opiates aren’t endorphins, and there isn’t any evidence that either directly help with depression. Opiate withdrawal causes depression, maybe that’s what these people are medicating.
In one of those cases it wouldn’t totally surprise me if the depression caused by withdrawl is a handy “excuse” being used, but the other one I am thinking of I know it was being used for depression (whether it works or not is another thing)
So are there non-opioid endorphin like drugs or not?
By definition, you cannot make an artificial endorphin. Endorphin means endogenous morphine. An endorphin is an opiate-like neurotransmitter created by the human body.
From Wikipedia:
Endogenous substances are those that originate from within an organism, tissue, or cell.
ETA: You need to clarify your question. If you are asking about non-opiate drugs that treat depression, there are plenty. If you are asking about non-opiate drugs that have the same mechanisms as opiates and endorphins, then no. Any drugs that shows affinity to opioid receptors would be considered an opiate.
Spicy food can theoretically have some effects:
From the wiki for capsaicin:
“It is common for people to experience pleasurable and even euphoriant effects from ingesting capsaicin. Folklore among self-described “chiliheads” attributes this to pain-stimulated release of endorphins, a different mechanism from the local receptor overload that makes capsaicin effective as a topical analgesic. In support of this theory, there is some evidence that the effect can be blocked by naloxone and other compounds that compete for receptor sites with endorphins and opiates.[30]”
Thanks for the link. I had thought the unpleasant effects on one’s gastrointestinal tract from “recreational doses” of gabapentin would outstrip any sense of euphoria. Silly me! Ah, the things folks will do to the rest of their bodies to avoid feeling even a hint of brain pain. (Says the nicotine fiend. 
)
Also, I was going from memory in my earlier post (I should know by now not to do that when posting to GQ) and need to correct something: Neurontin was originally developed for the treatment of epilepsy. It subsequently was found effective in treating postherpetic neuralgia. My apologies.
Is there something that could act “further on” than the opiate receptor. I.e. presumably the opiate receptor being “triggered” does X,Y, and Z - maybe a drug could do Y and Z but not X, or whatever.
I don’t mean broad side effects by X,Y, and Z - I am talking about the specific things that the opioid receptors, er, do
It’s a complicated topic, I’ve a lot I could say on it, but time constraints may prevent me. I’ll answer more if/when I can.
Briefly: opioids (and endorphins) are not antidepressants, they’re more along the line of anxiolytics (in addition to their pain-relieving, euphoria-inducing, and other activities.) Anxiety meds are notoriously bad for treating depression. Reducing anxiety/increasing euphoria does not relieve most depressions. It makes many of them worse.
And finding a way to reduce pain via opioid receptors without activating the euphoria/anxiolytic pathways appears very, very, VERY difficult. If possible at all.