A Phase 2 interventional study of Psilocybin and Diphenhydramine in Alcohol Dependence, sponsored by NYU Langone Health. Completed at 2 sites in United States. Open to participants aged 25 Years to 65 Years. Per ClinicalTrials.gov, last updated 2022-11-08.
Sponsored by NYU Langone Health · Phase 2, Interventional, and Treatment
Several lines of evidence suggest that classic hallucinogens such as psilocybin can facilitate behavior change in addictions such as alcohol dependence. The proposed investigation is a multi-site, double-blind active-controlled trial (n = 180, 90 per group) contrasting the acute and persisting effects of psilocybin to those of diphenhydramine in the context of outpatient alcoholism treatment.
Two to four sites will participate in this study. Aims of the study are 1) to characterize the acute effects of PO psilocybin 25 mg/70 kg, 30 mg/70 kg, and 40 mg/70 kg in alcohol dependent patients; 2) to evaluate the effect of psilocybin treatment on drinking outcomes for 32 weeks after the first administration, relative to diphenhydramine control; 3) to test whether or not characteristics of the drug administration session experiences mediate effects of psilocybin on short-term (1 week) persisting effects and post-session drinking behavior, 4) to evaluate the explanatory value of changes in alcohol craving, self-efficacy, motivation, and other psychological domains in accounting for the observed experimental effect of psilocybin relative to diphenhydramine control, and 5) to evaluate pre-post changes in drinking in participants after they receive psilocybin in the third session.
The total duration of psychosocial treatment in the double-blind period will be 12 weeks, and double-blind drug administration sessions will occur after 4 and 8 weeks. In the first psilocybin session, a dose of 25 mg/70 kg will be administered. Depending on the response in the first session, the dose for the second session may be increased to 30 mg/70 kg or 40 mg/70 kg, or held at 25mg/70kg. The dose of diphenhydramine will start at 50 mg, and may be increased to 100 mg or held at 50 mg in the second session, depending on response in the first session. Following completion of the double-blind period (34 weeks after randomization) all participants who meet interim safety criteria will be offered an additional session in which psilocybin will be administered. The drug will be administered during 8-hour sessions in an outpatient setting under close medical and psychiatric monitoring. The drug administration sessions will occur in the context of an extended version of Motivational Enhancement Therapy (Motivational Enhancement and Taking Action, META) with the addition of standardized preparation before and debriefing and follow-up after the psilocybin administration sessions. Extensive screening and baseline assessment will be completed, including thorough safety screening and assessment of participant characteristics that could potentially moderate treatment response. Within-session and short-term persisting effects will be assessed. Drinking outcomes and changes in several potential mediators of treatment effect, including motivation, self-efficacy, craving, depression, anxiety, and spiritual dimensions of the experience, will be measured until 50 weeks after the first drug administration session, for a total of 54 weeks from the initiation of treatment.
1,606 studies on the registry are indexed under Alcoholism; 329 are open to participants now.
This study's enrollment of 95 is close to the median of 87 across 1,371 interventional studies indexed under Alcoholism.
Browse Alcoholism studies →NYU Langone Health is the lead sponsor of 1,391 studies on the registry; 254 are open to participants now.
Of its 227 completed or terminated interventional studies of FDA-regulated products, 191 (84%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Psilocybin 25 mg/70 kg PO administered at week 4, 25-40 mg/70 kg PO administered at week 8.
Drug: Psilocybin · Behavioral: Motivational Enhancement and Taking Action (META)
Diphenhydramine 50 mg PO administered at week 4, 50-100 mg PO administered at week 8.
Drug: Diphenhydramine · Behavioral: Motivational Enhancement and Taking Action (META)
Manualized psychosocial intervention based on motivational enhancement therapy, functional analysis, and implementation of a change plan.
Percent of Heavy Drinking Days
The Timeline Follow-back (TLFB) method is used to calculate the percent of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
Time frame: Screening (Week 0)
Percent of Heavy Drinking Days
The Timeline Follow-back (TLFB) method is used to calculate the percent of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
Time frame: Baseline (Week 4)
Percent of Heavy Drinking Days
The Timeline Follow-back (TLFB) method is used to calculate the percent of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
Time frame: Follow Up (Weeks 5-36)
Drinks Per Day
The Timeline Follow-back (TLFB) method is used to calculate drinks per day. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
Time frame: Screening (Week 0)
Drinks Per Day
The Timeline Follow-back (TLFB) method is used to calculate drinks per day. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
Time frame: Baseline (Week 4)
Drinks Per Day
The Timeline Follow-back (TLFB) method is used to calculate drinks per day. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
Time frame: Follow Up (Weeks 5-36)
Percent of Drinking Days
The Timeline Follow-back (TLFB) method is used to calculate the percentage of days that participants drank alcohol. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
Time frame: Screening (Week 0)
Percent of Drinking Days
The Timeline Follow-back (TLFB) method is used to calculate the percentage of days that participants drank alcohol. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
Time frame: Baseline (Week 4)
Percent of Drinking Days
The Timeline Follow-back (TLFB) method is used to calculate the percentage of days that participants drank alcohol. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
Time frame: Follow Up (Weeks 5-36)
Short Inventory of Problems (SIP-2R) Score
15-item self-report questionnaire assessing problems related to alcohol use. Items are ranked on a 4-point Likert scale ranging from 0 (never) to 3 (daily or almost daily). The total score range is 0-45; the higher the score, the more problems related to alcohol use.
Time frame: Baseline (Week 4)
Short Inventory of Problems (SIP-2R) Score
15-item self-report questionnaire assessing problems related to alcohol use. Items are ranked on a 4-point Likert scale ranging from 0 (never) to 3 (daily or almost daily). The total score range is 0-45; the higher the score, the more problems related to alcohol use.
Time frame: Week 36
Percentage of Participants Achieving Abstinence From Drinking
The Timeline Follow-back (TLFB) method is used in calculating abstinence from drinking. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Abstinence is defined as zero drinks of alcohol over the target period.
Time frame: From Week 5 (1 week after first drug administration) up to Week 36
Percentage of Participants Achieving Abstinence From Drinking
The Timeline Follow-back (TLFB) method is used in calculating abstinence from drinking. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Abstinence is defined as zero drinks of alcohol over the target period.
Time frame: From Week 33 up to Week 36
Percent of Participants Achieving No Heavy Drinking Days
The Timeline Follow-back (TLFB) method is used in calculating the number of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
Time frame: From Week 5 (1 week after first drug administration) up to Week 36
Percent of Participants Achieving No Heavy Drinking Days
The Timeline Follow-back (TLFB) method is used in calculating the number of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
Time frame: From Week 33 Up to Week 36
Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 1 Level
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
Time frame: From Week 5 (1 week after first drug administration) up to Week 36
Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 1 Level
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
Time frame: From Week 33 Up to Week 36
Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 2 Levels
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
Time frame: From Week 5 (1 week after first drug administration) up to Week 36
Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 2 Levels
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
Time frame: From Week 33 Up to Week 36
Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 3 Levels
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
Time frame: From Week 5 (1 week after first drug administration) up to Week 36
Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 3 Levels
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
Time frame: From Week 33 up to Week 36
| Milestone | Psilocybin | Diphenhydramine |
|---|---|---|
| Started | 49 | 46 |
| Completed | 48 | 45 |
| Not completed | 1 | 1 |
| Withdrew: Elevated blood pressure | 1 | 1 |
The Timeline Follow-back (TLFB) method is used to calculate the percent of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
| percentage of days | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Heavy Drinking Days | 56.48 ± 31.77 | 48.57 ± 28.73 |
The Timeline Follow-back (TLFB) method is used to calculate the percent of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
| percentage of days | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Heavy Drinking Days | 24.11 ± 26.29 | 21.31 ± 20.14 |
The Timeline Follow-back (TLFB) method is used to calculate the percent of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
| percentage of days | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Heavy Drinking Days | 9.71 ± 26.21 | 23.57 ± 26.67 |
The Timeline Follow-back (TLFB) method is used to calculate drinks per day. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
| drinks per day | Psilocybin | Diphenhydramine |
|---|---|---|
| Drinks Per Day | 5.2 ± 2.81 | 4.38 ± 2.39 |
The Timeline Follow-back (TLFB) method is used to calculate drinks per day. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
| drinks per day | Psilocybin | Diphenhydramine |
|---|---|---|
| Drinks Per Day | 2.77 ± 2.3 | 2.19 ± 1.98 |
The Timeline Follow-back (TLFB) method is used to calculate drinks per day. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
| drinks per day | Psilocybin | Diphenhydramine |
|---|---|---|
| Drinks Per Day | 1.17 ± 1.99 | 2.26 ± 2.02 |
The Timeline Follow-back (TLFB) method is used to calculate the percentage of days that participants drank alcohol. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
| percentage of days | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Drinking Days | 78.03 ± 27.02 | 71.68 ± 28.98 |
The Timeline Follow-back (TLFB) method is used to calculate the percentage of days that participants drank alcohol. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
| percentage of days | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Drinking Days | 52.98 ± 31.78 | 45.99 ± 30.4 |
The Timeline Follow-back (TLFB) method is used to calculate the percentage of days that participants drank alcohol. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period.
| percentage of days | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Drinking Days | 29.39 ± 32.86 | 42.83 ± 33.43 |
15-item self-report questionnaire assessing problems related to alcohol use. Items are ranked on a 4-point Likert scale ranging from 0 (never) to 3 (daily or almost daily). The total score range is 0-45; the higher the score, the more problems related to alcohol use.
| score on a scale | Psilocybin | Diphenhydramine |
|---|---|---|
| Short Inventory of Problems (SIP-2R) Score | 20.26 ± 8.89 | 21.6 ± 9.61 |
15-item self-report questionnaire assessing problems related to alcohol use. Items are ranked on a 4-point Likert scale ranging from 0 (never) to 3 (daily or almost daily). The total score range is 0-45; the higher the score, the more problems related to alcohol use.
| score on a scale | Psilocybin | Diphenhydramine |
|---|---|---|
| Short Inventory of Problems (SIP-2R) Score | 6.59 ± 8.8 | 13 ± 10.48 |
The Timeline Follow-back (TLFB) method is used in calculating abstinence from drinking. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Abstinence is defined as zero drinks of alcohol over the target period.
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percentage of Participants Achieving Abstinence From Drinking | 22.9 | 8.9 |
The Timeline Follow-back (TLFB) method is used in calculating abstinence from drinking. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Abstinence is defined as zero drinks of alcohol over the target period.
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percentage of Participants Achieving Abstinence From Drinking | 47.9 | 24.4 |
The Timeline Follow-back (TLFB) method is used in calculating the number of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Participants Achieving No Heavy Drinking Days | 33.3 | 11.1 |
The Timeline Follow-back (TLFB) method is used in calculating the number of heavy drinking days. The TLFB is a method for assessing the number of drinks of alcohol on a daily basis over the previous 30 days. For each day in the recall period, the participant indicates the number of drinks of alcohol they consumed. The TLFB provides a calendar prompt and number of other memory aids (e.g., holidays, payday, and other personally relevant dates) to facilitate accurate recall of drug use during the target period. Heavy drinking is defined as ≥4 drinks per day for women and ≥5 drinks per day for men.
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Participants Achieving No Heavy Drinking Days | 62.5 | 40 |
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 1 Level | 83.3 | 71.1 |
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 1 Level | 89.6 | 64.4 |
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 2 Levels | 60.4 | 40 |
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 2 Levels | 60.4 | 40 |
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 3 Levels | 29.92 | 13.3 |
For men, WHO low risk drinking (level 1) is defined as \>0 grams of alcohol/day (g/d) to 40 g/d; moderate risk (level 2) as \>40 g/d to 60 g/d; high risk (level 3) as \>60 g/d to 100 g/d; and very high risk (level 4) as \>100 g/d. For women, low risk (level 1) is defined as \>0 g/d to 20 g/d; moderate risk (level 2) as \>20 g/d to 40 g/d; high risk (level 3) as \>40 g/d to 60 g/d; and very high risk (level 4) as \>60 g/d. Abstinence was defined as no risk (level 0).
| Percentage of participants | Psilocybin | Diphenhydramine |
|---|---|---|
| Percent of Participants Achieving WHO Risk Drinking Level Decrease of at Least 3 Levels | 37.5 | 17.8 |
Collected over After first medication administration (week 4) through week 36.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Psilocybin | 0/48 (0%) | 0/48 (0%) | 37/48 (77.1%) |
| Diphenhydramine | 0/45 (0%) | 2/45 (4.4%) | 29/45 (64.4%) |
| Event | Psilocybin | Diphenhydramine |
|---|---|---|
| Mallory-Weiss SyndromGastrointestinal disorders | 0/48 | 1/45 |
| Suicidal IdeationPsychiatric disorders | 0/48 | 1/45 |
| Event | Psilocybin | Diphenhydramine |
|---|---|---|
| HeadacheNervous system disorders | 21/48 | 2/45 |
| NauseaGastrointestinal disorders | 10/48 | 4/45 |
| AnxietyPsychiatric disorders | 7/48 | 1/45 |
| Suicidal IdeationPsychiatric disorders | 4/48 | 2/45 |
| PainGeneral disorders | 1/48 | 3/45 |
| BronchitisInfections and infestations | 0/48 | 3/45 |
| Viral upper resp. tract infectionInfections and infestations | 2/48 | 3/45 |
| Back painMusculoskeletal and connective tissue disorders | 1/48 | 3/45 |
| Depressed moodPsychiatric disorders | 3/48 | 2/45 |
| InsomniaPsychiatric disorders | 3/48 | 2/45 |
| Age, Continuous(years) | Psilocybin | Diphenhydramine | Total |
|---|---|---|---|
| Mean | 46.94 ± 10.91 | 44.24 ± 12.15 | 45.59 ± 11.53 |
| Sex: Female, Male(Participants) | Psilocybin | Diphenhydramine | Total |
|---|---|---|---|
| Female | 20 | 21 | 41 |
| Male | 28 | 24 | 52 |
| Ethnicity (NIH/OMB)(Participants) | Psilocybin | Diphenhydramine | Total |
|---|---|---|---|
| Hispanic or Latino | 6 | 8 | 14 |
| Not Hispanic or Latino | 42 | 37 | 79 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Psilocybin | Diphenhydramine | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 1 | 1 |
| Asian | 3 | 0 | 3 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 3 | 1 | 4 |
| White | 37 | 36 | 73 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 5 | 7 | 12 |
| Region of Enrollment(Participants) | Psilocybin | Diphenhydramine | Total |
|---|---|---|---|
| United States | 48 | 45 | 93 |
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