I have never heard of such problems pertaining to Kratom use. If you can cite those claims, I would like to read about it.
The only health problems I have heard of is possible respiratory depression with excessive doses, which I do not believe is proven as of yet.
Hey, guys. I know that it's been eight years since this post, but I just wanted to add my experiences with kratom in case somebody comes along and finds this. I know this isn't an ~official source~, but this DID happen, and no, I'm not trolling. I actually just created this account in order to share my experience.
So, I started taking kratom in June 2016 so that I could get off opiates. At first, everything was fine - but then, a few days later, I started experiencing signs of serious liver dysfunction. I became extremely jaundiced (I wish I had taken a picture to prove it, but it didn't occur to me at the time). My feet and legs started swelling up - my doctor told me that it was just because it was summer, so I didn't think it was a problem at the time. I had a fever, I was throwing up every few hours (I hadn't vomited in over fifteen years prior to this), and my feet were so fucking itchy that I had to keep them submerged in water for about three days straight, because otherwise they were just driving me completely insane.
I didn't put it all together until my feet began itching - I rationalized away all of my other symptoms, even the jaundice (I thought I was imagining it). After that, I did a bit of research online about kratom and sound a few sources indicating that it occasionally can cause acute liver failure in people who are taking it, and I stopped taking it for a while. The entire kratom community completely disowned me, accused me of trolling, and even argued that I must have secretly been taking some other type of drug to cause this reaction. I didn't - I was taking ONLY kratom at the time, nothing else. Not any other kind of medication, not even Tylenol.
Just kratom. But, of course, they need to deny that kratom can have serious reactions (even though it's extremely rare) to "prove" that there's nothing wrong with it. They made me doubt myself at the time, so I began taking it again about two weeks later, at a much lower dose (1 tsp at a time).
This past weekend, I just realized that I'm suffering from low-level liver abnormalities again. The kratom, at a much lower dose, is causing it, I'm sure - again, I'm not taking any other medications at all. M feet have been swollen for about a week. I wasn't jaundiced, but I did start vomiting again. My hands were twitching. I've been experiencing significant memory loss since April, which I've only recently begun to realize, but I thought it was normal. The night I figured it out, it was because I had just taken some kratom about 45 minutes before, and began to experience extreme confusion and paranoia - just for one example, I thought the fridge was rapping.
Please understand that I'm not trying to attack kratom or people who take it, or suggesting that it should be illegal. Kratom is clearly a live-saver for people who are trying to get clean, especially those who don't want to try methadone or suboxone due to the prolonged withdrawals. Everybody has a different experience with kratom - it just so happens that my personal experience was a very bad one, and I just want to warn you guys about it so that you know what's going on if you take kratom and end up experience signs of liver dysfunction.
Here are a few studies about hepatoxicity in kratom users, for those of you who will doubt this story and argue that I must have just had something else. My doctor agreed that it was most likely the kratom, since I neither take any other drugs, and nor do I have Hepatitis C or anything else they can find. I also started re-experiencing these symptoms after continuing to use kratom, so that's the most likely explanation.
http://www.ncbi.nlm.nih.gov/pubmed/21528385
http://link.springer.com/article/10.1007/s13181-011-0155-5
http://onlinelibrary.wiley.com/doi/10.1002/hep.27612/full
(Incidentally, I have also experienced respiratory depression as a result of kratom too. You know that feeling of when you take opiates and wake up the next morning with that fluid feeling in your lungs? I experienced that on kratom as well.)
(No, I'm not a hypochondriac.)