Kratom living monograph
Onset, main effects, after-effects, and the substantially longer pharmacokinetic phase.
Time course
Subjective effects end well before complete elimination. Timing estimates concern oral leaf products and do not transfer to extracts or enriched 7-OH.
often about 15–45 min
Food, gastric emptying, product, and formulation can shift onset.
about 30–90 min
Early redosing can underestimate the exposure that appears later.
often around 1–2 h
Human PK data show alkaloid-dependent plasma peaks roughly between 1 and 4.5 hours; plasma peak and subjective peak are not identical.
often about 3–6 h
Sedation, nausea, or impairment may persist longer.
variable, sometimes into the next day
Especially with frequent use, high concentrations, co-use, or sleep loss.
In a study of six healthy participants, terminal half-lives for different alkaloids were roughly 12 to 45 hours. A multiple-dose study also found complex, alkaloid-dependent profiles. This does not mean the main effects remain noticeable for that long, but it helps explain accumulation with frequent use.
Pharmaceutics, 2022Molecules, 2024Trust
Each source is tied to a claim domain. “Reviewed” means editorial source review—not individual medical clearance.
Drug and Alcohol Dependence · 2017
Contributes: Large online survey of use patterns and self-reported effects.
Limit: Self-selection, self-report, no product analysis, and no causal inference.
Pharmaceutics · 2022
Contributes: Analysed 2 g leaf product; human PK for multiple alkaloids.
Limit: Only six healthy participants and one low exposure; not generalisable to extracts.
Molecules · 2024
Contributes: Controlled human PK using 0.5–4 g of analysed dried leaf.
Limit: Small healthy sample, specific study product, and disclosed industry conflicts.
