Cannabis Use and Perception

(PISCES Trial)

Overseen By Carillon Skrzynski, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Colorado, Boulder

Must not be taking: Substance use, Psychotic disorders

Disqualifiers: Pregnancy, Other drug use, others

Compensation: Varies

Number of Visits: 2

Duration: 1 week

166 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how cannabis affects mood, cognition, and physical sensations, including temperature and pain. Participants will experience different water temperatures to assess their interaction with cannabis use. Two groups will be involved: one using warm water and the other using cold water. The trial suits individuals who use cannabis regularly (at least once a week) and sometimes rely on it for coping. Participants must also occasionally use CBD products and have no history of using certain other drugs. As an unphased trial, this study provides a unique opportunity to contribute to understanding cannabis effects in everyday users.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you cannot participate if you are using medications for substance use or psychotic disorders.

What prior data suggests that water temperature variation is safe for participants?

Research shows that cold water immersion carries some risks. Sudden immersion, particularly in water below 60 degrees Fahrenheit, can trigger a reaction called cold shock. This reaction may cause gasping, a faster heartbeat, and sometimes confusion.

For individuals with heart problems, this can be dangerous. Frequent exposure might also raise blood pressure, potentially affecting heart health over time. Consulting a doctor before attempting cold water immersion is important, especially for those with health concerns.

In summary, while researchers study cold water immersion for potential benefits, it does present risks. Participants should consider these factors and consult a healthcare provider if necessary. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about exploring water temperature variation as a method to understand cannabis use and perception because it's a novel approach that doesn't rely on introducing new substances to the body. Unlike traditional treatments for managing cannabis use, which may involve pharmacological interventions or behavioral therapies, this method simply uses warm and cold water to investigate their effects on perceptions. This approach could uncover new insights into how external sensory experiences can influence cannabis use and perception, potentially offering a non-invasive and drug-free strategy to support individuals in managing their cannabis consumption.

What evidence suggests that water temperature variation is effective for studying cannabis use and perception?

This trial will compare the effects of cold water and warm water immersion. Research has shown that cold water immersion can impact stress and recovery. Studies have found that it triggers a stress response, increasing heart rate and blood pressure while reducing calmness. This may alter mood and feelings, which could be significant for cannabis users. Cold water immersion also aids recovery by reducing swelling and enhancing overall well-being. These effects may explain its study alongside cannabis use for its potential to influence mood and feelings. ^{6 7 8 9 10}

Are You a Good Fit for This Trial?

This study is for individuals who use cannabis, with or without a history of cannabis abuse, and are interested in how it affects their mood, thinking, perception of temperature and pain, as well as heart rate. Participants will be involved for about one week.

Inclusion Criteria

I use CBD+THC or CBD products at least once a month.

Endorsement of at least moderate use of cannabis for coping purposes (≥2.5 on CMMQ)

I am between 21 and 65 years old.

Exclusion Criteria

Report of other drug use (cocaine, opiates, methamphetamine) in the past 90 days or fail urine screen for any of these drugs

I am not pregnant, trying to conceive, or breastfeeding.

Diagnosis or use of medications for substance use or psychotic disorders

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1 week

Treatment

Participants engage in cannabis use and complete various tasks to assess mood, cognition, perception, and physiological responses

1 week

2 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

1 week

What Are the Treatments Tested in This Trial?

Interventions

• Water Temperature Variation

Trial Overview The trial is exploring the impact of smoking cannabis on mental and physical responses by varying water temperatures (CW and WW) during tests. It involves two visits over a week totaling around 2.5 hours to complete the tasks.

How Is the Trial Designed?

Group I: Cold Water Experimental Treatment 1 Intervention

Group II: Warm Water Placebo Group 1 Intervention

Who Is Running the Clinical Trial?

University of Colorado, Boulder

Lead Sponsor

Trials

128

Recruited

29,600+

National Institute on Drug Abuse (NIDA)

Collaborator

Trials

2,658

Recruited

3,409,000+

Published Research Related to This Trial

Cannabis use is increasing due to decriminalization and legalization, but its adverse effects, including cardiovascular and pulmonary issues, as well as links to malignancy and neuropsychiatric disorders, are becoming more evident despite limited research.

The rise in cannabis use among minors has led to more cases of overdose and toxicity, highlighting concerns about its safety, particularly regarding impaired driving and motor vehicle accidents.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Adverse Impact of Cannabis on Human Health. Chandy, M., Nishiga, M., Wei, TT., et al.[2023]

In a study involving 20 participants (10 frequent and 10 occasional marijuana users), different doses of THC (0.2, 0.4, and 0.6 mg/kg) showed minimal impact on objective performance in sensory and perceptual motor tests, indicating that THC does not significantly impair cognitive function.

However, THC produced significant subjective effects, such as changes in mood and perception, especially in occasional users, suggesting that its primary impact may be on the autonomic nervous system rather than higher cognitive processes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Sensory, perceptual, motor and cognitive functioning and subjective reports following oral administration of delta9-tetrahydrocannabinol. Peters, BA., Lewis, EG., Dustman, RE., et al.[2020]

Inhalation of THC using an e-cigarette technology produced significant hypothermic effects in Sprague-Dawley (SD) rats compared to Wistar (WI) rats, indicating strain differences in response to THC despite similar plasma levels of the substance.

The antinociceptive (pain-relieving) effects of inhaled THC were consistent across both rat strains, suggesting that while the hypothermic response varies, the pain-relieving properties of THC remain effective regardless of the strain used.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of Δ⁹-tetrahydrocannabinol (THC) vapor inhalation in Sprague-Dawley and Wistar rats. Taffe, MA., Creehan, KM., Vandewater, SA., et al.[2022]

Long-term recreational cannabis use may lead to an increased risk of undesirable side effects, challenging the public perception of cannabis as a safe substance.

Despite its medical potential, there is a need for caution and further research into the adverse health effects associated with regular nonprescribed cannabis use, as these risks are often underreported.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Shifting the Paradigm on Cannabis Safety. Bannigan, P., Evans, JC., Allen, C.[2022]

Cannabinoid-based medicines, particularly THC and CBD, have been associated with common side effects like dizziness and fatigue, and THC may impair cognitive functions and psychomotor skills, which is important for activities like driving.

The safety profiles of cannabinoid-based treatments are complex and require careful consideration of potential drug interactions and individual patient assessments, emphasizing the need for evidence-based prescribing practices.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety Considerations in Cannabinoid-Based Medicine. Gottschling, S., Ayonrinde, O., Bhaskar, A., et al.[2020]

Between 2012 and 2017, adverse events (AEs) related to recreational cannabis use in France increased significantly, with reports tripling from 179 to 562 cases, highlighting a growing concern about its safety, particularly among young men aged 18-34.

The study identified a range of AEs, with dependence being the most common (10.1% to 20.3% over the years), and noted the emergence of cannabinoid hyperemesis syndrome, indicating serious health risks associated with chronic cannabis use.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Adverse events of recreational cannabis use reported to the French addictovigilance network (2012-2017). Bouquet, E., Pain, S., Eiden, C., et al.[2021]

In a study involving 217 subjects across 10 different studies, THC was found to evoke distinct subjective effects categorized into three clusters: perception (feeling high), relaxation (drowsiness and mental slowness), and dysphoria (suspicious thoughts).

The feeling of being high was identified as the strongest predictor of THC's effects, suggesting that understanding these subjective experiences can help differentiate the roles of endocannabinoid systems in health and disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Profiling the subjective effects of Δ⁹-tetrahydrocannabinol using visual analogue scales. Kleinloog, D., Roozen, F., De Winter, W., et al.[2021]

High doses of THC (8.0 mg/kg) in male rats led to significant decreases in locomotion and body temperature, indicating a strong hypothermic and hypoactive response, likely due to metabolic inhibition in the brain.

Lower doses of THC (0.5 and 2.0 mg/kg) produced milder effects on behavior and temperature, resembling the effects of diazepam, suggesting that THC's impact may vary based on dosage and the state of the animal.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Behavioral and temperature effects of delta 9-tetrahydrocannabinol in human-relevant doses in rats. Smirnov, MS., Kiyatkin, EA.[2021]

In a study of 168 non-treatment-seeking heavy drinkers, cannabis users experienced a greater reduction in negative feelings when consuming alcohol compared to non-cannabis users, suggesting a unique subjective response to alcohol.

This finding indicates that cannabis use may influence risk factors for developing alcohol use disorder (AUD) by altering how individuals respond emotionally to alcohol, particularly in terms of negative affect.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cannabis use and subjective response to alcohol in the human laboratory. Nieto, SJ., Venegas, A., Hudson, J., et al.[2023]

Clinical studies on cannabis administration are essential for understanding its effects and developing treatments for cannabis dependence, with different methods of administration (smoking, oral, intravenous) each having unique safety and efficacy profiles.

Acute adverse effects from cannabis can include tachycardia, cognitive impairment, and anxiety, necessitating careful screening and monitoring of participants to ensure safety during research studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Methods for clinical research involving cannabis administration. Gorelick, DA., Heishman, SJ.[2019]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10403841/

Cannabis use for exercise recovery in trained individuals Contrast water therapy, or alternating hot- and cold-water immersion, has demonstrated the ability to enhance perceived recovery, perceived ...

2. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/40515781/

Does acute stress induced via cold water immersion ... Does acute stress induced via cold water immersion increase blood THC concentrations in regular cannabis users?

3. researchgate.net researchgate.net/publication/372936156_Cannabis_use_for_exercise_recovery_in_trained_individuals_a_survey_study

(PDF) Cannabis use for exercise recovery in trained ... Ninety-three percent of participants felt that CBD use assisted them with recovery from exercise, while 87% of participants felt the same regarding THC use.

4. researchgate.net researchgate.net/publication/392694774_Does_acute_stress_induced_via_cold_water_immersion_increase_blood_THC_concentrations_in_regular_cannabis_users

(PDF) Does acute stress induced via cold water immersion ... Results CWI produced a small but significant stress response, characterised by increased HR and systolic BP and decreased subjective “calmness”.

5. journals.plos.org journals.plos.org/plosone/article?id=10.1371/journal.pone.0317615

Effects of cold-water immersion on health and wellbeing This systematic review suggests that CWI delivers time-dependent effects on inflammation, stress, immunity, sleep quality, and quality of life.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9518606/

Health effects of voluntary exposure to cold water If repeated cold-water immersion causes elevation of blood pressure, this could be linked to several heart conditions, such as ventricular ...

7. heart.org heart.org/en/news/2022/12/09/youre-not-a-polar-bear-the-plunge-into-cold-water-comes-with-risks

You're not a polar bear: The plunge into cold water comes ... The National Center for Cold Water Safety warns that sudden immersion in water under 60 degrees Fahrenheit can kill a person in less than a ...

8. medicalnewstoday.com medicalnewstoday.com/articles/ice-bath-benefits

Ice bath benefits, risks, and safety explained Ice baths and other types of cold-water immersion have risks, including cold shock and hypothermia. A person should consider consulting a doctor ...

9. share.upmc.com share.upmc.com/2025/08/ice-bath-health-risks/

What Are the Health Risks of Ice Baths? Discover the potential side effects of overextending and overusing ice baths, and what these cold plunges can mean for your long-term ...

10. weather.gov weather.gov/safety/coldwater

Cold Water Hazards and Safety Unplanned immersion in cold water can be life-threatening for anyone without protection from the temperatures or a lifejacket to help you stay afloat. When Cold ...