If you have time, an painkiller/opiate guide would be an interesting read by someone with your knowledge.
If i have time i could put something together, but in general you'll develope a tolerance both to the pink killing effects as well as the "high/euphoria". Im reluctant to use the term "high" when referring to opiates, since it's more of a warm blanket-feeling of contentment. "High" i tend to associate with something like weed, which is a dissociative (dissacoiates your mind from reality). Keep in mind that drugs/medications affect people differently. For instance many people get sleepy and nod off with opiates, whereas with me they "woke me up" and i functioned perfectly normal and never made me tired and allowed me to work 5/530am till midnight, get home and get to bed by 1/130am, wake up 4/430am and repeat.
Opiate withdrawal sucks. The withdrawal differs between particular opiates. Heroin/morphine/oxycodone/hydromorphone/oxymorphone withdrawal isnt nearly as bad as methadone or nubain/torbugesic/temgesic(which can last 45+ days). Tramadol/Ultram is unique because it works on 9-13 areas in the brain. In addition to being an opiate agonist/antagonist, it's also a (among other things...) Selective Serotonin Reuptake Inhibitor (SSRI) and Selective Norepinephrine Reuptake Inhibitor (SNRI) such as Celexa and Effexor, both of which cause shitty, unexpected withdrawal if you happen to miss a dose.
Another shitty part about opiates is that the tolerance stays with you for a long time. For instance, about a month ago i had kidney stones. I suffered through the first couple days, but i had shit to do that couldnt wait, so i bit the bullet and picked up some Percocet. Took 30mg that afternoon and felt nothing. Next day pain was worse... Long story short, 160mgs at once barely made my nose itch although it made so i could stand up outnof a chair without my back feeling like it was going to break (kidney stones give me pain at the very bottom of my lumbar spine... Passing the stones is nothing compared to the 3-5days of pain prior to passing them). 160mgs of oxycodone is a big dose, & keep in mind i hadnt had any opiates for 9+months. Another instance/example would be back in 2003 i was hospitalized for 10 days with pancreatitis and given 1-2mg Diluadid iv every few hours. That 2mg would have me about as "high" as ive ever been and id go from laying on my side in the hospital bed, unable to stand without curling over clutching my stomach , to unplugging my iv unit and walking down to the cafeteria and eating (going against the dr-ordered liquid only diet. Opiates make me hungry as fuck)... Fast forwad to a couple years ago, towards the end of my relapse (aside from the 10days of painkillers in the hospital i was clean from opiates from about dec 2001 till about june 2015 (or 2014? I forget), i ran out of diacetyl-morphine and was in withdrawal, but found some Diluadid. Remember 2mg had an enormous effect on me before.... Now? I shot 24mg iv and i was still in withdrawal. Same thing happened after that and instead of diluadid, i took 240mg oxycodone crushed up at once,& again, was still in withdrawal.
So, to summarize, opiates are always a lose-lose situation... Unless you have terminal cancer and youre gonna die and just want to be comfortable until it's time.
This is training... Learn to embrace the pain and discomfort.
*i forgot one thing... CBD oil/vape/edibles or whatever. Ive seen promising reports/studies on it being beneficial to athletes as an antiinflamatory/pain-reliever. However ive not used it myself. A lady i used to date happens to be the supplier for 90% of all dispensaries in the desert (5'2" red haired 53yr old latina with f-cup boobs lol)... So maybe I'll hit her up for a CBD vape pen and see how it works.
*far as i know, CBD is non-psychoactive, unlike THC.