^ I would recommend staying from extracts, as they are far too expensive, even if you get them from good online vendors. And yes, Kratom and tramadol are a nice mix, but I would not eat any stimulating variety of Kratom while on anything more than 150mg of tram. Also, while on more than 8-10g of Kratom, if you dose more than once a day, then don't take any tramadol.
My preferred dosage when mixing the two was no more than 75-100mg of tram and 4-6g of good quality Kratom. Taken all at once, you get to enjoy the Kratom high, whose yomhimbe-like effects synergize with the NRI and SRA effects of tramadol, and, just as the opioid portions (mitragynine, 7-OHM) of the Kratom high start to wind down at the 3 hour mark, the converted O-Desmethyltramadol (for which tramadol acts as prodrug for, when used an as opioid) being converted from the tramadol starts reaching high enough levels to ensure no drop off in high or pain relief.
Be very careful mixing the two, and please take my dosage suggestions seriously, as I have plenty of experience with the two. In fact, they're my two favorite opioids/opiates. Just know that tramadol already lowers the seizure threshold with its 5-HT releasing and NRI effects, and Kratom also adds to the stimulant effect, further lowering the seizure threshold. Add on top of all this, that O-Desmethyltramadol and Kratom have opioid activity, and the seizure threshold is yet again lowered. Delta opioid agonists, like mitragynine (found in Kratom) or bupe, also lower seizure thresholds...
So, not as dangerous as mixing CNS stimulants with tramadol, and safe when both used in moderation, but it's definitely risky when you overdo both. If you found that you took too much tramadol one day (more than 200mg+), I would stay far, far away from Kratom.