Most of the psychoactive effects of kratom have evolved from anecdotal and case reports. Kratom has an unusual action of producing both stimulant effects at lower doses and more CNS depressant side effects at higher doses.

• Stimulant effects manifest as increased alertness, boosted physical energy, talkativeness, and a more social behavior.
• At higher doses, the opioid and CNS depressant effects predominate, but effects can be variable and unpredictable.

Reviews from consumers and the public who have used kratom report lessened anxiety, stress, and fatigue, pain relief, sharpened focus, and relief of withdrawal symptoms. Beside pain, other anecdotal uses include as an anti-inflammatory, antipyretic (to lower fever), antitussive (cough suppressant), antihypertensive (to lower blood pressure), as a local anesthetic, to lower blood sugar, and as an antidiarrheal. It has also been promoted to enhance sexual function. It's important to note that none of these uses have been studied clinically or are proven to be safe or effective.

It has been reported that opioid-addicted individuals use kratom to help avoid narcotic-like withdrawal side effects when other opioids are not available. Kratom withdrawal side effects may include irritability, anxiety, craving, yawning, runny nose, stomach cramps, sweating and diarrhea - all similar to opioid withdrawal.

Mixing kratom, other opioids, and other types of medication can be dangerous. Kratom has been shown to have opioid receptor activity, and mixing prescription opioids, or even over-the-counter medications such as loperamide, with kratom may lead to CNS depression and serious side effects.