and, from wikipedia:
"Effects come on within five to ten minutes after use, and last for several hours. The feeling has been described as happy, strong, and active, with a strong desire to do work."
Yep. A strong desire to do work.
and "Side effects, although rare, may include dry mouth, increased or decreased urination, loss of appetite, and nausea or vomiting. Heavy use can result in a prolonged sleep. Possible side effects from long term use include anorexia and weight loss, insomnia, and dependence. Comprehensive scientific and clinical studies have yet to be conducted to establish the potential health risks associated with consistent long term consumption of kratom."
"Most of our knowledge about Kratom risks and dangers is still based on the oral tradition of Asian villagers, however: people that possibly would not know about any kratom side effects associated with let us say schizophrenia or high blood pressure - for the simple reason that these people until today would hardly ever diagnose such conditions and also because most illnesses frequent in the western world are unknown to them. But recent western research into kratom side effects have not supported any assumptions that would allow conclusions to serious side effects or dangers of kratom for healthy people and infrequent/moderate consumption.
We do however definitely know that daily use of kratom over extended periods of time will lead to dependence. Kratom dependence then will lead to a desire for higher doses in shorter intervals and finally require withdrawal. Withdrawal symptoms have been reported as unpleasant and lasting several days - which is to say that Kratom dependence is far less serious than more common addictions as to nicotine, alcohol or sleeping pills.
Still it has to be said that kratom is nothing to be consumed on a daily base like i.e. coffee. Even as a close relative to the coffee plant, Kratom is much stronger than coffee and does not warrant daily consumption.
Long-term daily high dose Kratom consumption is also reported to induce nervousness, sleeplessness, loss of libido, constipation and the darkening of skin complexion.
Just as any other herbal remedy, or as a matter of fact any kind of drug, Kratom can be overdosed. Kratom overdoses can cause serious conditions. The known risks and dangers of Kratom overdoses include hallucinations, delusions, listlessness, tremors, aggression, constipation and nausea. "