At many different times i my life I have been addicted to heroin and other opiates/opioids. These have been some of the gloomiest must unpleasant times of my life, definitely weren't good for my mental or physical health for multiple and complex reasons, and definitely weren't good for my sex drive either. I have also seen and continue to see heroin in particular tear apart some of the people I love the most in this world. I do not regret saying goodbye to opiate addiction. However, I am glad I went there, and it was my personal choice to stop, I didn't have to. I always encourage any efforts I see my friends to cut down or stop, but only because it is coming from them.
And I do still occasionally enjoy opiates very much, particularly opium tea I make from super potent poppies that grow in a local park (night time raids jumping over fences, stealth operation, loads of fun). I will occasionally smoke a little bit of heroin if its offered but this is naturally getting less and less. And kratom for sure.
But for me, kratom doesn't sit all that neatly along more standard opiates, both pharmacologically and because of it has quite a unique character in my experience. Of course, if you abuse it you will end up in the same boat. When I got seriously addicted to benzodiazepines about two and half years ago I realised it wasn't to do with opiates or any drug that has go the grip of me, it was me and the addictive monster that lives inside of me. I am now fine I am able to enjoy pretty much any drug that I was previously a slave to on occasion and not be pulled back down into the pit which is great, with the exception of benzos which were the most recent uncoupling, perhaps the most destructive and by far the most difficult to withdraw from (you don't want to go there, believe me).
Anyway, sorry for the long post, I am not brilliant at saying things in a very succinct way. In my limited experience, occasional use of kratom has never given me dark circles under the eyes, my sleep actually improves when I take it and you can see that in my face afterwards. But I don't have anything to say about anything close to regular use because I have never gone there. I guess my point is that it may be the addiction and the way it makes you behave that is more or at least equal in causing things like dark circles under the eyes (although not with sex drive and similarly more obviously chemically connected side effects) but of course I can't be sure. I am pretty sure the worst I have ever looked was after a serious crack bender rather than when i was dependent on opiates. Feel free to come back with your own evidence and experience, just a theory based on my own limited experience.
