A Phase 1/2 interventional study of Cannabidiol (CBD) only and Placebo only in PTSD, Post Traumatic Stress Disorder and Suicide, sponsored by Leslie Lundahl. Not yet recruiting at 1 site in United States. Open to participants aged 18 Years to 60 Years. Per ClinicalTrials.gov, last updated 2026-08-26.
Sponsored by Leslie Lundahl · Phase 1/2, Interventional, and Treatment
The overall strategy is to recruit veterans with PTSD who report minimal current cannabis use but are interested in or considering therapeutic cannabis to manage mental health symptoms (anxiety, depression, PTSD and/or suicidality). The information gained from this study could lead to the development of new treatments for persons who suffer from post-traumatic stress disorder and maintain better mental health.
The total time commitment estimated per participant is 20 study visits. This is approximated below:
Visit 1: Screening Consent and Screening Assessments: During this visit the potential participant will learn about the study procedures and sign the screening informed consent documents, then complete screening measures which will include a clinical interview (i.e., assessments of PTSD and other psychiatric diagnoses, suicidality, medical history, etc.), a physical examination, and various questionnaires. At this time, they will collect blood, urine, breathalyzer and saliva samples.
Visit 2: Study consent and Baseline Assessments: During this visit the participant will be asked to read the study informed consent form and will have an opportunity to have any questions answered before agreeing to participate in the study. Particular attention will be given to reviewing required procedures and possible side effects of the drugs (THC and CBD) with participants.
Visit 3: Pre-Treatment Behavioral Tests and Magnetic Resonance (MR) Scan: During this visit the participant will complete several computer tasks, and the study staff will be measuring reaction time and psychophysiological measures. The tasks that the participant will perform will show three different images and an aversive stimulus (e.g. which will be a mild electric shock to the ankle paired with a snake hissing sound of an animated snake) may follow one image most of the time, while the other images may never be followed by the aversive cue. The participant will need to try to predict whether the aversive cue will occur or not based on which image is shown and will be asked to repeatedly rate on a scale how likely it is that he or she thinks an aversive cue will occur after each image. Lastly, during the session the participant will also be asked to report his or her level of anxiety on a scale from 0 to 100.
Visit 4: Pre-Treatment Behavioral Tests with MR Scan: This visit will be very similar to Visit 4. Participants will participate in the same type of task inside the MR scanner, while the study staff measures reaction time and psychophysiological responding and brain activation. Participants will view the same images he or she did previously and may experience the same aversive stimulus as during Visit 3. Participants will again be asked to rate how much they expect to experience the aversive stimulus after each image and will also be asked to report their level of anxiety on a scale from 0 to 100.
Visit 5\&6: Prolonged Exposure (PE) Sessions 1 \& 2: These sessions will consist of psychoeducation that includes discussion or reactions to trauma, treatment rationale, breathing retraining, and review of the Subjective Units of Distress Scale (SUDS) to assess level of distress from 0 to 100 (100=extreme anxiety/distress) when facing fears. One session occurs weekly across 2 weeks.
Visit 7-10: Prolonged Exposure (PE) Sessions 3-6: These sessions will consist of repeated exposures to trauma memories (imaginal exposure) and avoided situations (in vivo exposure). As is standard, patients will also practice exposures (e.g., listen to tapes of imaginal exposure, carry out in vivo exposure) outside of PE sessions as "homework". At exposure-focused sessions either cannabis or placebo (PBO) will be administered just before the session. One session occurs weekly across 8 weeks.
Visit 11: Prolonged Exposure (PE) Session 7: This visit is similar to the ones above, but it will include a mid-treatment assessment and there won't be any cannabis or placebo administration.
Visit 12-14: Prolonged Exposure (PE) Sessions 8-10: These sessions will consist of repeated exposures to trauma memories (imaginal exposure) and avoided situations (in vivo exposure). As is standard, patients will also practice exposures (e.g., listen to tapes of imaginal exposure, carry out in vivo exposure) outside of PE sessions as "homework". One session occurs weekly across 8 weeks.
Visit 15: Post-Treatment Assessments: This visit will include a review of therapeutic gains, relapse prevention, and assessments.
Visit 16: Post-Treatment Behavioral Tests and MR Scan: This visit will be very similar to Visit 3. Participants will participate in the same type of task inside the MR scanner, while the study staff measures reaction time and psychophysiological responding and brain activation. Participants will view the same images he or she did previously and may experience the same aversive stimulus as during Visit 3. Participants will again be asked to rate how much they expect to experience the aversive stimulus after each image and will also be asked to report their level of anxiety on a scale from 0 to 100.
Visit 17: Post- Treatment Behavioral Tests and MR Scan: This visit will be very similar to Visit 4. Participants will participate in the same type of task inside the MR scanner, while the study staff measures reaction time and psychophysiological responding and brain activation. Participants will view the same images he or she did previously and may experience the same aversive stimulus as during Visit 5. Participants will again be asked to rate how much they expect to experience the aversive stimulus after each image and will also be asked to report their level of anxiety on a scale from 0 to 100.
Visit 18: 3-Month Follow-Up Treatment Assessment: This session is similar to Visit 15 and will include review of therapeutic gains, relapse prevention, and assessments.
Visit 19: 6-Month Follow-Up Treatment Assessment: This session is similar to Visit 18 and will include review of therapeutic gains, relapse prevention, and assessments.
Visit 20: 9-Month Follow-Up Treatment Assessment: This session is similar to Visit 19 and will include review of therapeutic gains, relapse prevention, and assessments.
2,682 studies on the registry are indexed under Stress Disorders, Post-Traumatic; 601 are open to participants now.
This study's planned enrollment of 280 is above the median of 69 across 2,196 interventional studies indexed under Stress Disorders, Post-Traumatic.
Browse Stress Disorders, Post-Traumatic studies →This is the only study on the registry with Leslie Lundahl as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cannabis with \<1mg THC and \<1mg CBD is administered and smoked immediately prior to exposure therapy sessions 3-6. 70 participants will be randomly assigned to this treatment arm. All participants will receive prolonged exposure therapy.
Drug: Placebo only
Cannabis with 2.5mg CBD is administered and smoked immediately prior to exposure therapy sessions 3-6. 70 participants will be randomly assigned to this treatment arm. All participants will receive prolonged exposure therapy.
Drug: Cannabidiol (CBD) only
Cannabis with 2.5mg THC is administered and smoked immediately prior to exposure therapy sessions 3-6. 70 participants will be randomly assigned to this treatment arm. All participants will receive prolonged exposure therapy.
Drug: Delta-9-tetrahydrocannabinol (THC) only
Cannabis with 2.5mg THC and 2.5mg CBD is administered and smoked immediately prior to exposure therapy sessions 3-6. 70 participants will be randomly assigned to this treatment arm. All participants will receive prolonged exposure therapy.
Drug: THC:CBD 1:1
Plant cannabis that will be smoked.
Also known as: Cannabis
Plant that will be smoked.
Plant cannabis that will be smoked.
Also known as: Cannabis
Plant cannabis that will be smoked.
Also known as: Cannabis
Treatment Response
Clinician Administered PTSD Scale for DSM-5 (CAPS-5 Score), anxiety, mood, suicidality, disability. The CAPS-5 is a clinician interview that determines the presence and severity of PTSD consistent with the Diagnostic \& Statistical Manual 5 (DSM-5) and allows for assessing changes in symptom severity over time. PTSD diagnosis is based on meeting the DSM-5 symptom cluster criteria (minimum threshold of symptoms with a score ≥ 2) with a qualifying criterion A index trauma. The CAPS-5 Total Severity Score is calculated by summing the total score for each of the four symptom categories to assess past-month PTSD symptoms on a specific traumatic event: intrusion (Category B), Avoidance (Category C), Mood and Cognition (Category D), and Hyperarousal (Category E). CAPS-5 Total Severity scores range from 0-80, where higher scores indicate worse PTSD severity.
Time frame: Through study completion, an average of 12 months
Brain measures
Functional magnetic resonance imaging (fMRI) will be used to measure blood oxygen level dependent (BOLD) changes in regions of interest (amygdala, ventromedial prefrontal cortex, hippocampus) during tasks.
Time frame: Pre and post treatment-Through study completion, an average of 12 months
Skin conductance response
Skin conductance is a measure of physiological arousal, it can be used to measure periods of heightened emotional responses to stimuli, here it is used to confirm fear conditioning.
Time frame: through study completion, an average of 12 months
Drug Effects Questionnaire (DEQ)
Subjective ratings of drug effects on from 1-5 on the following scale: "feel", "high", and "like"
Time frame: through study completion, an average of 12 months
Visual Analogue Scale of Mood (VAS)
Subjective ratings of mood and drug effects on a 0-100 scale. Higher numbers on the scale reflect stronger experiences of different mood and drug effects. Each item is scored individually. There is no overall score.
Time frame: through study completion, an average of 12 months
Quality of Life Inventory (QOLI)
assessment of well-being and satisfaction of life. The questionnaire is a 32-item scale ranging from -6 (extreme dissatisfaction) to +6 (extreme satisfaction). Scores range from 1-77 with higher scores indicating higher life satisfaction.
Time frame: through study completion, an average of 12 months
Pittsburgh Sleep Quality Index (PSQI)
Used to evaluate overall sleep quality. Participants rate sleep quality on a 4 point scale from 0 - "not during the last month" to 3 - "three or more times per week" relating to various sleep concerns. Scores range from 1-21 with higher scores indicating worse sleep quality.
Time frame: through study completion, an average of 12 months
Epworth Sleepiness Scale (ESS)
assessment of daytime sleepiness in adults. Participants rate feeling sleepy during various activities on a 4 point scale from 0 - "no chance of dozing" to 3 - "high chance of dozing". Scores range from 0-24 and are characterised as follows: 0-7:It is unlikely that you are abnormally sleepy. 8-9:You have an average amount of daytime sleepiness. 10-15:You may be excessively sleepy depending on the situation. You may want to consider seeking medical attention. 16-24:You are excessively sleepy and should consider seeking medical attention.
Time frame: through study completion, an average of 12 months
Brief Pain Inventory (BPI)
assessment of the severity of pain and its impact on functioning. The scale consists of nine questions with a mixture of visual analogue scales and written answers. Questions 3-6 measure current pain levels on a scale from 1 - "no pain" to 10 "pain as bad as you can imagine" with higher ratings suggesting greater levels of pain (range 0-40). Question 9 has 7 nested questions (rated from 0 - 'Does not interfere" to 10 - "Completely interferes") relating to how much pain is interfering with mood, everyday tasks and sociability (range 0-70), a higher rating indicates greater issues arising from pain.
Time frame: through study completion, an average of 12 months
Short form 36
assessment of general health questions. Each question is scored on a range from 0-100 with higher scores indicating a more favourable health state.
Time frame: through study completion, an average of 12 months
fMRI
using fMRI we can look at the differences between individuals during fear processing responses.
Time frame: through study completion, an average of 12 months
Psychophysiology
Skin conductance response (SCR): change in SCR \[peak amplitude from 0.5-4.5 sec following stimulus presentation minus average 2 second baseline prior to stimulus presentation\].
Time frame: through study completion, an average of 12 months
DNA analysis
Plasma samples collected are analyzed for genetic and epigenetic markers of endocannabinoid system functioning.
Time frame: through study completion, an average of 12 months
Cannabinoid concentration - Blood
As well as measuring drug levels during treatment, blood samples allow us to track the activity of the endocannabinoid system throughout the treatment. A novel approach to determine whether Delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) function differently in the endocannabinoid system.
Time frame: through study completion, an average of 12 months
Urine Drug Toxicology tests
Urine samples are also provided on regular visits for drug testing.
Time frame: through study completion, an average of 12 months
Cannabinoid concentration - Saliva
As well as measuring drug levels during treatment, these samples allow us to track the activity of the endocannabinoid system throughout the treatment. A novel approach to determine whether Delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) function differently in the endocannabinoid system.
Time frame: through study completion, an average of 12 months
TLFB
The Timeline Follow-Back (TLFB) will be used to record the time of cannabis use and route of administration as well as any alcohol and other drug use.
Time frame: Administered at every study visit, besides fMRI scanning visits.
Blood pressure
Both systolic and diastolic pressure will be assessed
Time frame: through study completion, an average of 12 months
Heart rate
Heart rate (bpm) will be assessed
Time frame: Throughout the 12-month study
Skin temperature
Skin temperature (in degrees Fahrenheit) will be assessed
Time frame: Throughout the 12-month study
Oxygen saturation
Oxygen saturation (percent oxygen in the blood) will be assessed with pulse oximeter
Time frame: Throughout the 12-month study
Plan to share: Undecided
Start is estimated for Sep 2026; primary completion for Sep 2031, 60 months later.
Of 17 phase 1/2 interventional studies under Stress Disorders, Post-Traumatic, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 17 and three quarters within 35. This study's planned 60 months is above that.
How these figures are worked out, and which studies are left out of them.
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Studies of the drug tested here: Cannabis sativa subsp. indica TOP
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