No, none at all! I have been a kratom person for almost 7 years. Kratom is nature's wonder herb. However, I keep my "burns" (in case you didn't know, when discussing kratom on other forums, you refer to a dose as a burn, as kratom is labeled NOT FOR HUMAN CONSUMPTION, just an incense.) Be careful of your kratom dosing, LESS is MORE when it comes to kratom. The best way is to use the smallest amount to achieve the desired effects. My "burns' are normally 1.5-2grams. I use a scale, that way I don't waste any or over due it. I read about lots of people who use WAY too much kratom per burn. Experiment with it and find your sweet spot..
If anyone on these forums has questions about kratom, I think I can answer almost all of them. Feel free to PM or post questions and I will answer.