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. 2025 Nov 9;17:100394. doi: 10.1016/j.dadr.2025.100394

Clinically characterizing adults who use kava or kratom: Substance use disorder assessment challenges for increasingly popular botanical products

Katherine Hill a, Edward W Boyer b, Kirsten E Smith c,⁎
PMCID: PMC12663646  PMID: 41322679

Abstract

Background

Kratom (Mitragyna speciosa) and kava (Piper methysticum) are psychoactive botanicals with growing popularity We aimed to characterize the clinical characteristics of people who have consumed these products.

Methods

We conducted an online survey of US adults who have used kava or kratom. Diagnostic and Statistical Manual-5 (DSM-5) substance use disorder (SUD) criteria were used to assess symptoms related to past-year kratom and/or kava use. Respondents were also asked to report on the compatibility of kava and kratom effects with daily living.

Results

Of the 367 participants, 91.3 % reported lifetime kratom use and 49.0 % reported lifetime kava use. There was substantial overlap of lifetime use of both substances (40.3 %). Past-year SUD diagnostic criteria for kratom were met by 38.1 % of participants; when this group was dichotomized by past-year kava use, those who also co-used kava had higher proportions of endorsing symptoms of “using more kratom than intended” and “needing to use larger amounts to feel the same effect” than those who used kratom without kava (p = 0.032 and p = 0.011, respectively). Meeting SUD criteria for kava was uncommon among those reporting past-year use (7.5 %), regardless of past-year kratom use. Kratom effects were perceived as helpful and compatible with daily living, though fewer reported this for kava effects.

Conclusions

Assessment of patients using kratom or kava may become challenging due to co-use. The relative rewarding and reinforcing effects of these botanicals alone or combined requires systematic study. SUD for either is possible but should be contextualized by patient-level factors including other substance use.

Keywords: Kratom, Mitragyna speciosa, Kava, Piper methysticum, substance use disorder

1. Introduction

Products derived from the psychoactive botanicals kratom (Mitragyna speciosa) and kava (Piper methysticum) have become widely available in the United States (US), often marketed as dietary supplements. These botanicals differ in their historical use and pharmacology, as well as their possible risk profiles. While kratom leaf, kava root, and simple, aqueous extracts of kava root have long been used in regions where they are native (Cinosi et al., 2015, Cox and Banack, 1991, Davis and Brown, 1999, Singh et al., 2015, Volgin et al., 2020), both botanicals are now sold in various product formulations across the US, typically at concentrations higher than preparations used indigenously or historically (Dufour et al., 2024, Grundmann et al., 2023). US-based prevalence estimates for kratom use range between < 1.0–9.1 %, whereas kava use prevalence remains undetermined (Grundmann et al., 2025, Palamar, 2021).

New blended products have appeared on the market that can neither readily be called “kratom” nor “kava” as botanicals are premixed for consumers (Spungen et al., 2024). These ready-to-consume coformulated kava-kratom products are in the form of flavored liquid shots or tonics. Further, a growing number of ethnobotanical tea bars in the US serve kava and kratom preparations made in-house (Piercey et al., 2025). The concurrent or contemporaneous use of these botanicals presents some possibilities meriting clinical attention.

As with any bioactive substance, kratom or kava use could result in adverse or toxic effects. This could occur for either botanical when used alone, particularly at higher doses, over a longer period of time, or on a frequent basis, but may be more likely when combined. For instance, kratom and kava possess chemical constituents that, when repeatedly co-ingested, may interact to increase the likelihood or severity of potential adverse events, including those related to the development of physical dependence or substance use disorder (SUD), which has been observed for each botanical alone (Bleifuss et al., 2025, Cassidy et al., 2024, Gnanasegaram et al., 2024, Rogers et al., 2024, Smith et al., 2024). Specifically, kratom has numerous alkaloids with mu-opioid (MOR) agonism (Berthold et al., 2022, Maxwell et al., 2020, Obeng et al., 2021), kappa and delta opioid antagonism (Kruegel and Grundmann, 2018), alpha-2 adrenergic agonism (Matsumoto et al., 1996), and, 5-HT1A agonism (León et al., 2021); though its dopaminergic actions are not fully elucidated.(Stolt et al., 2014); (Vijeepallam et al., 2019); (Yusoff et al., 2022) Bioactive natural constituents of kava, kavalactones, bind weakly at GABA-A receptors with effects attributed to blockade of sodium and calcium channels, blockade of reuptake of norepinephrine and dopamine, MAO-B inhibition, and GABAA-enhancing mechanisms distinct from benzodiazepines. (Chua et al., 2016, Davies et al., 1992, Pluskal et al., 2019) Collectively, the MOR and polypharmacy activity of kratom and sedative-hypnotic-like behavior of kava suggest the possibility of mutually reinforcing properties that may potentially exacerbate risk of coformulated products or of drinks prepared in bars using both psychoactive botanicals (Piercey et al., 2025).

Kratom use has received greater scrutiny than kava in the US, including real-world assessments of polysubstance use, compatibility of effects with daily living, and disordered use (Covvey et al., 2020, Grundmann, 2017, Rogers et al., 2022, Smith et al., 2024). Diagnostic and Statistical Manual (DSM-5) SUD modified for kratom (kratom use disorder, KUD) has been evaluated in surveys and case reports (Hill et al., 2024, Schmuhl et al., 2020, Smith et al., 2022, Smith et al., 2024, Stanciu et al., 2021, Swart et al., 2024). To our knowledge, there are no published assessments of SUD modified for evaluating kava use (kava use disorder, KavUD).

1.1. Aims

Due to the rising popularity of kratom and kava we sought to identify characteristics of US adults who reported any lifetime use and to examine clinical characteristics associated with past-year use of either or both botanicals. Data abstracted for this report come from a larger survey of psychoactive substances marketed as dietary supplements. Here, we present a subset of findings on kava and kratom relevant to clinicians. Other findings related to use patterns are presented elsewhere.

2. Methods

2.1. Data collection

Our cross-sectional online survey collected data between December 2023 and July 2024. Digital flyers advertising substances of interest were distributed online (e.g, X, Reddit). Kava- and kratom-specific flyers were used along with flyers mentioning both botanicals (“Have you ever used kava or kratom?”). Data were collected anonymously using Qualtrics. Participants were informed about the survey prior to participation and were uncompensated. IP addresses were collected to verify geographic location and to prevent “ballot-stuffing.” Due to its confidential nature, the Johns Hopkins University School of Medicine Institutional Review Board determined this did not qualify as human subjects’ research.

2.2. Survey

The survey was developed from prior kratom surveys with additional items adapted for assessment of kava (Hill et al., 2025, Rogers et al., 2024). We provide the full survey instrument in Supplemental Materials. Sections germane to this report include demographic characteristics, lifetime and past-year substance use, preferred substances, DSM-5 assessment for past-year SUD for kava and kratom, quit attempts, adverse events, and perceived compatibility of kava or kratom effects with daily living.

2.3. Sample

For the full survey eligibility, participants had to be > 18 years of age and to endorse lifetime use of one of the following substances: kratom, kava, akuamma seed, and/or tianeptine. We included cases in our analyses only if a participant reported lifetime use of kratom and/or kava and if all survey validity checks were passed. To characterize demographic and historical substance use characteristics, we stratified data into three mutually exclusive groups: (1) lifetime use of kratom but not kava use, (2) lifetime use of kava but not kratom, and (3) lifetime use of both botanicals. To examine clinical characteristics, including SUD, of the sample as they relate to kratom use and kava use, we dichotomized the dataset by past-year use of kratom with and without contemporaneous past-year kava use (and past-year use of kava with and without contemporaneous past-year use of kratom).

2.4. Data analyses

As this study was exploratory, we generated summary statistics. To detect global differences between the three mutually exclusive groups, we used an ANOVA test for continuous variables; a Fisher Exact test or a Chi Square test for categorical variables was used, depending on cell sizes. To detect differences between kratom consumers with/without lifetime use of kava and kava consumers with/without lifetime use of kratom, we used t-tests for continuous variables and either a Fisher Exact test or a Chi Square test for categorical variables. Data were analyzed using SAS 9.4 (SAS Institute Inc., Cary, NC).

3. Results

A total of 406 adults completed the survey. Four cases were removed for not providing an age of > 18 years; 33 were removed for completing the survey in an unrealistically short amount of time (< 5 min). Of the 369 valid respondents, 2 were removed for never having used kava or kratom. Of this final sample (N = 367), 40.3 % (n = 148) reported lifetime use of both kava and kratom; 51.0 % (n = 187) reported lifetime kratom, but not kava use; and 8.7 % (n = 32) reported lifetime kava, but not kratom use.

3.1. Participant demographic characteristics

Participants who reported both lifetime kava and kratom use (Table 1) were slightly younger on average (mean=37.4 years) compared to those with lifetime kratom-only use or kava-only use (mean=42.3 and mean=41.1 years, respectively, p = 0.001). Those reporting lifetime kava-only use had the lowest proportion of White individuals (75.0 %, p = 0.007), whereas those reporting kratom-only use in their lifetime had the highest proportion (93.1 %). Employment was also statistically different between groups (p = 0.004), with those reporting both kava and kratom use in their lifetime having the highest proportion of individuals working or in school (83.8 %). Having received medication for opioid use disorder was highest among respondents who reported lifetime kratom use without kava (13.37 %); any SUD history tended to be more common among respondents who had used kratom.

Table 1.

Characteristics of participants reporting lifetime kratom use, lifetime kava use, and both lifetime kratom and kava use (N = 367).

LifetimeKratomUse (No Kava Use)
(n = 187) 		LifetimeKavaUse (No Kratom Use)
(n = 32) 		Lifetime Use ofBothKava and Kratom
(n = 148) 		p-value*
Age Mean (SD) 42.30 (13.00) 41.13 (15.49) 37.36 (9.99) 0.001
N % N % N %
White/Caucasian 174 93.05 24 75.00 132 89.19 0.007
Male 114 60.96 22 68.75 89 60.14 0.675
Employment 0.004
Working full-time, working part-time, or a student 133 71.12 24 75.00 124 83.78
Disabled 19 10.16 2 6.25 17 11.49
Unemployed 18 9.63 3 9.38 5 3.38
Retired 17 9.09 3 9.38 2 1.35
Education 0.139
Finished High School / GED 19 10.16 3 9.38 12 8.11
Some College 40 21.39 5 15.63 31 20.95
College Degree or Higher ᵇ 121 64.71 22 68.75 105 70.95
Other 7 3.74 2 6.25 0 0.00
Income 0.780
< $30,000 53 28.34 7 21.88 31 20.95
$30,000 to less than $60,000 36 19.25 6 18.75 28 18.92
$60,000 to less than $90,000 32 17.11 5 15.63 29 19.59
> $90,000 66 35.29 14 43.75 60 40.54
Geographic Location ᵈ 0.837
Urban 74 44.85 13 56.52 73 49.66
Suburban 58 35.15 7 30.43 47 31.97
Rural 33 20.00 3 13.04 27 18.37
Ever Diagnosed with an SUD or Addiction 54 28.88 4 12.5 43 29.05 0.185
Believes to Have Ever Had an SUD or Addiction 0.184
Never 68 36.36 20 62.50 58 39.19
A long time ago, but not now 50 26.74 5 15.63 43 29.05
Recently, but not now 24 12.83 2 6.25 18 12.16
Currently 45 24.06 5 15.63 29 19.59
Ever Received Buprenorphine or Methadone 25 13.37 0 0.00 9 6.08 0.010
Currently in SUD Recovery 48 25.67 3 9.38 43 29.05 0.062
Interested in SUD Recovery 63 33.69 6 18.75 46 31.08 0.242
Kratom ranked in top 5 preferred substances 157 83.96 - - 122 82.43 0.170
Kava ranked in top 5 preferred substances - - 24 75.00 72 48.65 0.007
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* p-value represents ANOVA global test for continuous variables, and either a Fisher Exact test or a Chi Square test for categorical variables, depending on cell sizes.

ᵃ Other Race/Ethnicity includes: Hispanic, Native American, including Native Alaskan or Pacific Islander, Biracial, Middle-Eastern, Asian, African American/Black, and/or Other Race/Ethnicity

ᵇ College Degree or Higher includes: Associates/Vocational Degree, Bachelor's Degree, Master's Degree, PhD, JD, MD, and/or DO

ᶜ In Relationship includes: Currently Married, or In Committed Partner Relationship (monogamous or polyamorous). Not in relationship includes Single and looking for a long-term partner, Single and looking only for short-term hook-ups and sex, Divorced, or Widowed.

ᵈ Based on Rural-Urban Commuting Area (RUCA) Codes. Participants provided their zip code, which were used to find corresponding RUCA code. A score of 1, 4, or 7 were categorized as urban; 2, 5, 8 were categorized as suburban; and 3, 6, 9, or 10 were categorized as rural. There are 33 missing values (n = 165, n = 23, and n = 147 for total values for the three columns).

3.2. Substance use history and preferences

Among those who had ever used kava and kratom, kava was ranked as a top five preferred substance by 48.7 % of respondents. For respondents who had used kava but not kratom, 75.0 % ranked kava as a top five preferred substance (p = 0.007). Alternatively, 84.0 % of lifetime kratom-only respondents ranked kratom in their top five preferred substances, and this was relatively maintained among those with both kava and kratom use in their lifetime with 82.4 % ranking kratom in their top five preferred substances.

Lifetime substance use was prolific. Caffeine, alcohol, nonmedical cannabis, combustible tobacco, prescription opioids, cannabidiol, e-cigarettes, antidepressants, and psychedelics were most common. Statistically significant differences (Table 2) across the three lifetime kratom/kava use groups were found for caffeine, combustible tobacco, e-cigarettes, cannabidiol, prescription opioids, nonmedical prescription opioids, nonprescribed amphetamines, Delta-8, Delta-10, phenibut, prescribed antipsychotics, racetams, and akuamma seed. Reported proportions of use were typically highest among those who endorsed both lifetime kava and kratom use and typically lowest among those with lifetime kava-only use. An exception was prescribed Suboxone, which was highest among the lifetime kratom-only group (11.8 %) but not used within the kava-only group (p = 0.037). Prevalence of prescription opioid use was higher among those with kratom use (69.5 % vs. 71.0 % vs. 25.0 %, respectively; p < 0.001).

Table 2.

Lifetime substance usea for participants reporting lifetime kratom use, lifetime kava use, and both lifetime kratom and kava use.

Lifetime Kratom Use (No Kava Use)
(N = 187)
 Lifetime Kava Use (No Kratom Use)
(n = 32)
 Lifetime Use of Both Kava and Kratom
(n = 148)
 p-value*
N % N % N %
Caffeine 176 94.12 30 93.75 148 100.00 0.003
Alcohol 168 89.84 28 87.5 138 93.24 0.388
Cannabis (not prescribed) 150 80.21 20 62.5 120 81.08 0.055
Combustible tobacco (e.g., cigarettes, cigars, hookah) 138 73.80 17 53.13 110 74.32 0.041
Prescription opioids (prescribed) 130 69.52 8 25.00 105 70.95 < 0.001
Cannabidiol (CBD) 103 55.08 15 46.88 115 77.70 < 0.001
E-cigarettes/vapes 98 52.41 9 28.13 94 63.51 < 0.001
Anti-depressants (prescribed) 97 51.87 13 40.63 91 61.49 0.052
Hallucinogens (e.g., LSD, mushrooms) 85 45.45 13 40.63 76 51.35 0.407
Powder cocaine 74 39.57 8 25.00 58 39.19 0.276
Prescription opioids (not prescribed) 72 38.50 4 12.50 61 41.22 0.006
Anti-anxiety drugs (prescribed) 70 37.43 9 28.13 69 46.62 0.079
Ecstasy/MDMA 66 35.29 8 25.00 57 38.51 0.347
Amphetamines (not prescribed) 62 33.16 4 12.50 55 37.16 0.027
Delta 8 THC 59 31.55 7 21.88 83 56.08 < 0.001
Anti-anxiety drugs (not prescribed) 59 31.55 9 28.13 56 37.84 0.375
Delta 10 THC 57 30.48 5 15.63 73 49.32 < 0.001
Amphetamines (prescribed) 43 22.99 8 25.00 30 20.27 0.767
DXM/dextromethorphan 40 21.39 5 15.63 32 21.62 0.737
Ketamine 31 16.58 6 18.75 23 15.54 0.899
Methamphetamine 30 16.04 3 9.38 23 15.54 0.707
Marijuana (prescribed) 29 15.51 8 25.00 28 18.92 0.380
Phenibut 25 13.37 4 12.50 41 27.70 0.003
Crack/rock/freebase cocaine 24 12.83 0 0.00 18 12.16 0.069
Suboxone/Subutex (prescribed) 22 11.76 0 0.00 9 6.08 0.037
Heroin 21 11.23 2 6.25 19 12.84 0.645
Fentanyl 19 10.16 1 3.13 11 7.43 0.415
Synthetic marijuana 18 9.63 3 9.38 13 8.78 0.963
Suboxone/Subutex (not prescribed) 17 9.09 1 3.13 13 8.78 0.689
DMT 17 9.09 4 12.50 22 14.86 0.237
Modafinil/Provigil (not prescribed) 14 7.49 6 18.75 17 11.49 0.113
Anti-psychotics (prescribed) 13 6.95 9 28.13 23 15.54 0.001
Methadone (not prescribed) 11 5.88 0 0.00 9 6.08 0.478
Racetams 8 4.28 4 12.50 18 12.16 0.014
Tianeptine Sodium 8 4.28 2 6.25 7 4.73 0.805
Tianeptine Sulphate 8 4.28 1 3.13 7 4.73 1.000
Bath salts 7 3.74 1 3.13 4 2.70 0.907
Methadone (prescribed) 7 3.74 0 0.00 4 2.70 0.726
Akuamma Seed 6 3.21 0 0.00 22 14.86 < 0.001
Anti-depressants (not prescribed) 5 2.67 1 3.13 6 4.05 0.748
Anti-psychotics (not prescribed) 5 2.67 1 3.13 4 2.70 1.000
Other 16 8.56 4 12.50 11 7.43 0.588
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* p-value represents ANOVA global test for continuous variables, and either a Fisher Exact test or a Chi Square test for categorical variables, depending on cell sizes.

ᵃ Participants could select multiple answer choices, so frequencies will be larger than total and percentages will sum to over 100 %.

3.3. Characteristics of past-year kratom use and kratom use disorder

Table 3 shows respondent characteristics for those who had used kratom within the past-year (N = 323), and this sample dichotomized by those with (31.6 %, n = 102) or without (68.4 %, n = 221) past-year kava use.

Table 3.

Clinical characteristics of kratom use among participants reporting past-year kratom use with and without past-year kava use (N = 323).

Past-Year Kratom Use (N = 323) Past-Year Kratom
Use,withoutPast-Year Kava Use
(N = 221) 		Past-Year Kratom Usewith
Past-Year Kava Use
(n = 102) 		p-value*
DSM−5 SUD Past-year Symptom Checklist forKratom N % N %
N 		%
Experienced cravings, strong desires, or urges for kratom. 103 31.89 66 29.86 37 36.27 0.251
Used kratom in larger amounts and/or over a longer period than intended. 80 24.77 47 21.27 33 32.35 0.032
Had physical or psychological withdrawal symptoms when kratom was stopped. 80 24.77 55 24.89 25 24.51 0.942
Kept using the same amount of kratom but didn't feel it as much. 79 24.46 48 21.72 31 30.39 0.092
Kept using kratom in order to avoid withdrawal symptoms. 74 22.91 52 23.53 22 21.57 0.697
Needed to use larger amounts of kratom to feel the same effect. 65 20.12 36 16.29 29 28.43 0.011
Made at least one unsuccessful attempt to cut down or control kratom use. 65 20.12 44 19.91 21 20.59 0.888
Spent a great deal of time on activities to get, use, or recover from kratom's effects. 44 13.62 27 12.22 17 16.67 0.279
Kept using despite knowing it was causing or worsening physical or psychological problems. 35 10.84 23 10.41 12 11.76 0.715
Kept using despite knowing it was causing or worsening social or interpersonal problems. 35 10.84 24 10.86 11 10.78 0.984
Kratom use repeatedly interfered with major role obligations (at work, school, or home). 25 7.74 17 7.69 8 7.84 0.962
Gave up or reduced important social, occupational, or recreational activities because of kratom use. 23 7.12 17 7.69 6 5.88 0.557
Repeatedly used kratom in situations where it was physically hazardous. 18 5.57 10 4.52 8 7.84 0.227
Past-year DSM−5 Kratom Use Disorder Severity ᵃ 0.492
None 200 61.92 143 64.71 57 55.88
Mild 60 18.58 38 17.19 22 21.57
Moderate 29 8.98 19 8.60 10 9.80
Severe 34 10.53 21 9.50 13 12.75
Kratom Quit Attempts After Period of Regular Use 0.690
Never 200 61.92 135 61.09 65 63.73
At least once 49 15.17 38 17.19 11 10.78
2–5 times 42 13.00 27 12.22 15 14.71
6–10 times 19 5.88 12 5.43 7 6.86
11–15 times 2 0.62 1 0.45 1 0.98
16–20 times 3 0.93 2 0.90 1 0.98
> 25 times 4 1.24 3 1.36 0 0.00
So many I can't recall 5 1.55 3 1.36 2 1.96
Kratom Quit Attempt (n=123) Was Successful 85 69.11 55 63.95 30 81.08 0.059
Ever had unpleasant experience/adverse effect from kratom 154 47.68 101 45.70 53 51.96 0.295
Among those who had unpleasant experience/adverse effect from kratom (n = 154), sought medical help 9 5.84 8 7.92 1 1.89 0.165
Compatibility of Kratom Acute Effects with Daily Obligations (n=312) 0.441
Kratom effects are compatible with my daily obligations and help me achieve them 256 82.05 172 81.13 84 84.00
Kratom effects are compatible with my daily obligations, though not especially helpful for them 36 11.54 24 11.32 12 12.00
Kratom effects are not compatible with my daily obligations 1 0.32 1 0.47 0 0.00
Kratom effects are not compatible with my daily obligations, and they sometimes undermine my ability to meet my daily obligations 6 1.92 4 1.89 2 2.00
None of these are quite true for me 9 2.88 7 3.30 2 2.00
I don't take enough kratom to know 4 1.28 4 1.89 0 0.00
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* p-value represents a comparison between kratom consumers with/without past-year use of kava, with either a Fisher Exact test or a Chi Square test for categorical variables, depending on cell sizes.

ᵃ Participants could select multiple criteria, which were based on the 11 components of the DSM-5 criteria for a substance use disorder diagnosis, adapted for kratom. If someone had 0–1 components, they were classified as having no use disorder for kratom. If someone had 2–3 components, they were classified as having mild use disorder for kratom. If someone had 4–5 components, they were classified as having moderate use disorder for kratom. If someone had 6 +  components, they were classified as having severe use disorder for kratom.

KUD criteria were met by 38.1 % (n = 103) of participants reporting any kratom use in the past year. The most commonly reported KUD criteria were cravings (31.9 %), using kratom in larger amounts or over a longer period of time than intended (24.8 %), tolerance (20.1–24.5 %), and withdrawal-related symptoms (22.9–24.8 %). Higher proportions of participants who used both botanicals endorsed symptoms of “using more kratom than intended” and “needing to use larger amounts of kratom to feel the same effect” than those who just used kratom without kava (p = 0.032 and p = 0.011, respectively).

KUD diagnostic threshold was met by a slightly greater proportion (44.1 %, n = 45) for respondents with past-year consumption of both kratom and kava. Although not statistically significant, the proportion of severe cases (e.g. meeting 6 + criteria for KUD) was slightly higher in this group than those with past-year kratom use without kava use (12.8 % vs 9.5 %, respectively). Alternatively, for respondents reporting past-year kratom use without kava use, KUD prevalence was lower, at 35.3 %.

Approximately half of respondents experienced an unpleasant experience or adverse effect that they attributed to kratom (n = 154, 47.7 %) with 9 seeking medical attention for adverse effects. Open text responses indicated common experiences included dizziness, nausea, vomiting, nervousness, and wobbly eyes, which have been reported elsewhere (Smith et al., 2023). In some cases, participants reported co-use with other substances (e.g., vaped nicotine or cannabis) or inadvertently consuming too much, particularly when initiating use.

3.4. Characteristics of past-year kava use and kava use disorder

The clinical characteristics of respondents who reported past-year kava use (N = 134), further dichotomized by past-year kratom use, are shown in Table 4. Past-year kratom use was common (n = 102, 76.1 %) among past-year kava consumers. Ultimately, meeting criteria for KavUD was uncommon among those with past-year kava use (n = 10, 7.5 %). The most frequently endorsed DSM-5 symptoms of KavUD were: using kava in larger amounts and/or over a longer period of time than intended (n = 10, 7.5 %), followed by cravings (n = 8, 6.0 %), and unsuccessful quit attempts (n = 7, 5.2 %). We detected no statistically significant differences in KavUD proportions between those with or without past-year kratom use; however, KavUD was severe for 2 people, both of whom had past-year kratom use.

Table 4.

Clinical characteristics of kava use among participants reporting past-year kava use with and without past-year kratom use.

Past-year Kava Use
(N = 134) 		Past-year Kava UsewithoutPast-Year Kratom Use
(n = 32) 		Past-year Kava UsewithPast-Year
Kratom Use
(n = 102) 		p-value*
DSM−5 SUD Past-year Symptom Checklist forKava N % N % N %
Use kava in larger amounts and/or over a longer period than intended. 10 7.46 2 6.25 8 7.84 1.000
Experienced cravings, strong desires, or urges for kava. 8 5.97 1 3.13 7 6.86 0.680
Made at least one unsuccessful attempt to cut down or control kava use. 7 5.22 1 3.13 6 5.88 1.000
Repeatedly used kava in situations where it was physically hazardous. 5 3.73 2 6.25 3 2.94 0.593
Had physical or psychological withdrawal symptoms when kava was stopped. 5 3.73 1 3.13 4 3.92 1.000
Spent a great deal of time on activities necessary to get, use, or recover from kava's effects. 5 3.73 0 0.00 5 4.90 0.338
Kept using the same amount of kava but didn't feel it as much. 4 2.99 1 3.13 3 2.94 1.000
Kept using kava in order to avoid withdrawal symptoms. 4 2.99 0 0.00 4 3.92 0.572
Kept using kava despite knowing it was causing or worsening physical or psychological problems for me. 3 2.24 1 3.13 2 1.96 0.562
Needed to use larger amounts of kava just to feel the same effect. 3 2.24 1 3.13 2 1.92 0.562
Kava use repeatedly interfered with major role obligations (at work, school, or home). 1 0.75 0 0.00 1 0.98 1.000
Kept using kava despite knowing it was causing or worsening social or interpersonal problems. 1 0.75 0 0.00 1 0.98 1.000
Gave up or reduced important social, occupational, or recreational activities because of kava use. 1 0.75 1 3.13 0 0.00 0.239
Past-year DSM−5 Kava Use Disorder Severity ᵃ 0.900
None 124 92.54 30 93.75 94 92.16
Mild 5 3.73 1 3.13 4 3.92
Moderate 3 2.24 1 3.13 2 1.96
Severe 2 1.49 0 0.00 2 1.96
Kava Quit Attempts After Period of Regular Use 0.647
Never 115 85.82 29 90.63 86 84.31
At least once 11 8.21 1 3.13 10 9.80
2–5 times 5 3.73 1 3.13 4 3.92
6–10 times 2 1.49 1 3.13 1 0.98
11–15 times 1 0.75 0 0.00 1 0.98
16–20 times/More than 25 times/So many I can’t recall 0 0.00 0 0.00 0 0.00
Kava Quit Attempt (n=19) Was Successful 17 89.47 3 100.00 14 87.50 1.000
Ever had unpleasant experience/adverse effect from kava 36 26.87 8 25.00 28 27.45 0.785
Among those who had unpleasant experience/adverse effect from kava (n = 36), sought medical help 1 2.78 0 0.00 1 3.57 1.000
Compatibility of kava acute effects with daily obligations(N=122) 0.101
Kava effects are compatible with my daily roles and obligations and help me achieve them 60 49.18 11 36.37 49 53.26
Kava effects are compatible with my daily roles and obligations, though not especially helpful for them 28 22.95 11 36.37 17 20.83
Kava effects are not compatible with my daily roles and obligations 4 3.28 1 3.33 3 3.26
Kava effects are not compatible with my daily roles and obligations, and they sometimes undermine my ability to meet them. 0 0.00 0 0.00 0 0.00
None of these are quite true for me 13 10.66 5 16.67 8 8.70
I don't take enough kava to know 17 13.93 2 6.67 15 16.30
Open in a new tab

* p-value represents a comparison between kava consumers with/without lifetime use of kratom, with either a Fisher Exact test or a Chi Square test for categorical variables, depending on cell sizes.

ᵃ Participants could select multiple criteria, which were based on the 11 symptoms of the DSM-5 criteria for a substance use disorder diagnosis, adapted for kratom. If someone had 0–1 components, they were classified as having no use disorder for kratom. If someone had 2–3 components, they were classified as having mild use disorder for kratom. If someone had 4–5 components, they were classified as having moderate use disorder for kratom. If someone had 6 +  components, they were classified as having severe use disorder for kratom.

Just under 15.0 % (n = 19) of past-year kava consumers had ever tried to quit kava, if only for a short period of time; 89.5 % (n = 17) were successful. We asked respondents to explain why they felt they were not successful in their kava quit attempts; participants noted reasons such as difficulties with withdrawal symptom management or simply missing kava.

Among past-year kava consumers, 26.9 % (n = 36) reported ever experiencing an unpleasant or adverse effect that they attributed to kava, with the proportion of self-reported adverse effects slightly higher among those who reported past-year kratom use (27.5 % vs. 25.0 %); of these, one person sought medical treatment for kava-related adverse effects. Respondents were asked to describe what occurred during their adverse event experience with as much detail as they wished; symptoms included vomiting, nausea, drowsiness, dizziness, agitation, diarrhea, and anxiety.

3.5. Compatibility of kratom and kava acute effects with daily roles and obligations

For both botanicals, we asked respondents to report the how the perceived effects fit within daily life, specifically if they were helpful and/or compatible with meeting daily roles and obligations. Most reported that kratom’s effects were helpful in meeting their daily roles and obligations (84.0 %), or if not helpful than at least compatible (12.0 %; Table 3). Kava was not reported as equally instrumental, with just over 50 % reporting kava’s effects as both helpful and compatible with daily role obligations; 12.0 % reported kava effects were compatible but not necessarily helpful (Table 4).

4. Discussion

Among respondents who had used both kratom and kava, more endorsed past-year SUD symptoms for kratom than for kava. In this sample, the severity of KUD was largely in keeping with prior survey results of mild to moderate (Hill et al., 2024, Smith et al., 2022). To our knowledge, ours is the first survey to assess SUD for kava. We not only found lower prevalence for meeting criteria for KavUD relative to KUD but also that fewer participants reported having ever experienced an adverse event that they attributed to kava, compared to kratom.

Despite the greater proportion of SUD criteria being met for kratom than for kava, the self-reported compatibility of kratom effects with daily living was far higher and less ambiguous than the perceived compatibility or helpfulness of kava. The ways in which kava use are incorporated into people’s lives may be more variable, with the effects of kava more consonant with recreational use and relaxation, (Piercey et al., 2025, Pont-Fernandez et al., 2023) rather than for instrumental use as has been evinced with kratom (Smith et al., 2024). For instance, many US adults who use kratom do so during their working hours for energy, focus, and productivity and find those effects to be largely compatible and helpful for daily living (Smith et al., 2022, Smith et al., 2022, Smith et al., 2024). Kava, despite being reported as a preferred substance among some kratom consumers, is not necessarily widely co-used in real-time among this population, relative to other substances such as nicotine, cannabis, or alcohol (Smith et al., 2024).

When examining consumer preference, while kratom may be both more preferred for possible psychoactive effects that are also more compatible with daily living compared to kava (e.g., perceived to help with one’s daily roles and obligations), these same factors may inadvertently result in the development of KUD following repeated consumption. Specifically, if kratom is simply being used more frequently and with less variability due to its compatibility with daily life (Rogers et al., 2024, Smith et al., 2024), then it may also possibly result in a greater likelihood of developing KUD over time. Further, kava use alone, particularly if infrequent, may be less likely to develop into KavUD by virtue of its effects being reserved for only certain times (i.e., evening, weekend) or if use is more recreational and less regimented and frequent (Pont-Fernandez et al., 2023, Smith et al., 2024). Ultimately, preference and use patterns for substances are informed by what substances are available at a given time along with availability of alternatives or substitutes (Acuff et al., 2024). The “set and setting” of use of these botanicals requires detailed investigation.

Still, the known pharmacology of these botanicals supports that, when used alone, kratom may be generally more compatible with more active rather than passive activities (Pont-Fernandez et al., 2023, Smith et al., 2023, Smith et al., 2024). Indeed, historically, kratom has been used by people in Southeast Asia doing intensive labor and who would benefit from its analgesic and stimulatory properties (Singh et al., 2016, Singh et al., 2017, Singh et al., 2022). Whereas historically kava has been used infrequently for cultural ceremonies, more recently consumers are seeking out its anxiolytic effects or using as part of social gatherings (Clough et al., 2000, Tecun et al., 2020). It is unclear how the consumption of kava alone or in social settings may alter the amount or frequency consumed. Physical dependence for kratom has been documented in Southeast Asia although, similar to kratom consumers in the US, psychosocial functioning has remined largely intact (Singh et al., 2015, Singh et al., 2019, Smith et al., 2024). In areas where kava is indigenous, it has been taken in mostly nonproblematic ways and largely in keeping with historical and cultural practices, but in recent years kava has also been identified as a substance of concern (Faleolo and Ravulo, 2019, Lemert, 1967, Mcdonald and Jowitt, 2000, Power et al., 2015, Shaver and Sosis, 2014).

4.1. Kava and kratom co-use: possible clinical complications

Insofar as kava is increasingly mixed and sold with kratom its perceived compatibility with daily roles and obligations may change, with kratom offsetting (or even enhancing) kava’s effects. Theoretically, this could lead to greater preference for kratom products containing kava and more regular or daily use.

In the absence of human abuse liability studies for kava or kratom, the addictive potential of either botanical – or their organic chemical constituents – remains unclear. Individually, kava and kratom have been previously associated with physical dependence, including withdrawal (Cassidy et al., 2024, Rogers et al., 2024, Smith et al., 2023, Smith et al., 2024, Swart et al., 2024). Although most kratom consumers appear to be functioning in ways uncharacteristic of moderate-severe addiction, some physical dependence symptoms can occur (Gnanasegaram et al., 2024, Reissig et al., 2024, Singh et al., 2015, Smith et al., 2023, Smith et al., 2024, Smith et al., 2024). However, among kratom-naïve adults, kratom leaf and mitragynine extract have not produced clear indicators of intoxication or drug demand, albeit these studies were not designed to adequately measure addiction liability against comparators (Prevete et al., 2025, Reissig et al., 2024).

It is important for consumers and clinicians to be mindful that the addiction liability of these two botanicals may change if co-used due to possible synergistic effects. This point is raised, in part, because kratom use is now a regular or daily event for many adults with new kratom-derived and kava-derived formulations proliferating alongside ethnobotanical tea bars serving kava and kratom (Boyer et al., 2008, Grundmann et al., 2023, Pont-Fernandez et al., 2023, Smith et al., 2022, Smith et al., 2024). In the past year, some blended kava-kratom products have received significant attention online and in the press (Bellamy, 2025, Reddy, 2025). It remains uncertain if coformulation of kava and kratom generates uniquely rewarding effects, or potentiation. At a minimum, though, the prolonged consumption of coformulated products poses challenges for clinical assessment and diagnosis. For instance, we found that even contemporaneous use of kratom and kava modestly increased the proportion of reported symptomology of many DSM-5 criteria for KUD and KavUD. Likewise prevalence for KUD was higher among those using both kava and kratom. If consumers exclusively use preformulated products it will be challenging for clinicians to assess for kava or kratom alone. Likewise, addressing withdrawal may be more challenging.

Another concern of growing demand for kava-kratom coformulated products or co-use of kava and kratom in ethnobotanical tea bars is the increased risk of toxicity not only from higher servings but also from poorly manufactured products, an area that receives less attention. For instance, the root of the kava plant is the only portion that can be consumed because aerial portions (e.g., leaves and stems) contain hepatotoxic chemicals (Clouatre, 2004, Teschke, 2010, Whitton et al., 2003). Increased global demand for these botanical-derived products may cajole growers to harvest kava root to maximize profit. In Southeast Asia, demand from US consumers may hasten kratom leaf harvests, impacting the leaf’s chemical composition (Kava, n.d.; (US Association Initiates Partnership In Kratom Export With Indonesia, 2022); (Laforest et al., 2023), which may be associated with its own set of risks. (Dorman et al., 2015, Feldman et al., 2023, Li et al., 2023).

4.2. Regulation, research, practice

The US Drug Enforcement Administration has not scheduled either botanical under the Controlled Substances Act (CSA), though some products are prohibited at state or local levels and some kratom-derived products containing 7-hydroxymitragynine have been recently recommended for scheduling (Hill et al., 2025, Smith et al., 2025). As botanicals, some kava and kratom formulations may satisfy regulatory standards required to be marketed in the US as dietary ingredients. This requires pre-market regulatory analyses by manufacturers regarding the specific identity and physiobiological properties of each kava and kratomingredient. It is unclear how many coformulated products satisfy a reasonable basis of safety. Policy on the regulation and sale of kratom and kava products, and coformulated products, remains in a confused state, with consumers, clinicians, and lawmakers lacking adequate data on new product formulations of these historically used botanicals. Indeed, some may make assumptions about the relative safety of these botanicals based on historical use (Baker, 2011). For kratom and kava individually, there may be sufficient data to inform regulation of each botanical as dietary supplements in certain formulations as research continues (McCurdy et al., 2024, Pittler and Ernst, 2003, Reissig et al., 2024, Smith et al., 2024, Smith et al., 2024, Tanna et al., 2022); but presently there are few published scientific data supporting safety claims about coformulated products (Dufour et al., 2024, Spungen et al., 2024). Despite risks, there is not widespread confirmed adverse events for co-formulated kava-kratom products or for either botanical alone that have been causally established relative to many illicit psychoactive substances, with some consumers using kava and/or kratom explicitly for harm-reduction or wellness purposes (Piercey et al., 2025, Smith et al., 2023). As such, the ultimate net benefit or harm related to use of these botanicals remains undetermined and is largely left up to consumers to weigh. Clinicians may also be uncertain on how best to treat KUD and/or KavUD symptoms due to the unique pharmacology of each alone, and particularly if combined (Smith et al., 2024).

4.3. Limitations

This cross-sectional study comprised a small convenience sample of kratom and kava consumers and cannot be generalized to all who use kratom or kava as person-level characteristics and within-population heterogeneity are always contributing factors. We also did not capture the extent to which either botanical was co-used (in real-time) with one another, which should be evaluated in future work. A limitation of this study is that past-year use was used to examine co-use relationships. Future assessments must capture real-time co-use. Lastly, participants reported symptoms and outcomes based on questions about individual substances, but in the context of polysubstance use there will be inevitable challenges in a person’s ability to attribute any outcome to a specific substance. This limitation underscores the need for not only more detailed clinical assessment but also the limitations of even the most rigorous assessments in an era where some psychoactive substances are only ever consumed together. A consumer could not be expected to report on the effects of either kava or kratom if used both were always used concomitantly.

5. Conclusions

As kava and kratom use persist in the US, and as some products are co-formulated to include both botanicals, clinicians must adopt more rigorous assessment methods and be attuned to the possibility of novel clinical presentations. For instance, if a patient has only ever used a product containing both kava and kratom, it will be impossible to assess them for a KUD or KavUD. Rather, the assessment would necessarily be product-specific. The implications for managing product-specific withdrawal or providing intervention will only become more fraught and complex as novel formulations of these (and other substances) proliferate further.

We urge clinicians to reconsider their assessment methods for substance use in light of a dramatically different landscape of psychoactive products than existed even several years ago (Hill et al., 2025). For instance, it may be more appropriate to ask a patient what brand they use within a class of products (e.g., cannabis, kava, kratom, 7-OH, etc.) to identify what chemical constituents it contains, and in what amounts. The variability of potency across products is also now significant (Grundmann et al., 2023, Smith et al., 2025). Such updates to assessment will need to be systemic (e.g., clinical software) to adequately capture all types of patient substance use.

CRediT authorship contribution statement

Katherine Hill: Writing – review & editing, Writing – original draft, Formal analysis. Edward W. Boyer: Writing – review & editing, Writing – original draft, Conceptualization. Smith Kirsten Elin: Writing – review & editing, Writing – original draft, Project administration, Data curation, Conceptualization.

Declaration of Competing Interest

Within the past two years KES and EWB have served as paid scientific advisors to the International Plant and Herbal Alliance though do not have active relationships. KES and EWB also serve as expert witnesses in legal cases involving kratom.

Footnotes

Appendix A

Supplementary data associated with this article can be found in the online version at doi:10.1016/j.dadr.2025.100394.

Appendix A. Supplementary material

Supplementary material

mmc1.docx (116.5KB, docx)

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