Clinical trial NCT05809453: Intranasal Cocaine and Temperature Regulation During Exercise
Official title: Intranasal Cocaine and Temperature Regulation During Exercise
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE1
PHASE2
Conditions: Hyperthermia
Cocaine Use
Exercise
Keywords: thermoregulation
sweating
skin blood flow
Lead sponsor: University of Texas Southwestern Medical Center
Sponsor class: OTHER
First posted: 2023-04-12
Enrollment: 12
Sex: ALL
Minimum age (years): 18
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: We will conduct a double-blind, placebo-controlled, crossover study. Following informed consent and screening, eligible participants will be randomized to complete the cocaine or the lidocaine (placebo) trial first, with the other "agent" administered during the subsequent visit. During these experimental visits, we will first obtain "pre-drug" temperature and cardiovascular data, which will be followed by administer of cocaine or lidocaine intranasally. Participants will then enter the chamber set to warm environmental conditions. After further instrumentation in the warm environment, participants will perform mild to moderate intensity physical activity for 60 minutes. Throughout the 60 minutes of physical activity we will record body temperature and cardiovascular responses. Upon concluding the physical activity, subjects will rest while body temperature and cardiovascular responses are obtained post-physical activity.
Primary purpose: BASIC_SCIENCE

Brief summary: Assess the effects of intranasal cocaine on temperature regulation and whole-body sweat rate during exercise in warm environmental conditions.

Detailed description: Previously it was shown that intranasal cocaine attenuates skin blood flow and sweating responses during passive heat stress, when compared to placebo. However, nothing is known about the effects of cocaine on whole-body temperature regulation during mild to moderate exercise in warm environmental condition.

This project will test the hypothesis that intranasal cocaine attenuates whole-body sweat rate, resulting in greater elevations in core temperature during mild to moderate exercise in warm environmental conditions.

Primary data include core temperature, skin temperatures, and whole body sweat rate. Secondary variables include cardiovascular responses, perceptions of exercise exertion and thermal comfort, and metabolic heat production. Intranasal lidocaine will be used as the placebo for cocaine. The selection of the drug administered during the first experimental trial will be randomized, with the other drug administered during the second experimental trial.

Eligibility criteria: Inclusion Criteria:

* 18 to 50 years of age
* Healthy
* Body mass index less than 31 kg/m\^2
* Speak English
* Systolic blood pressure \<140 mmHg
* Diastolic blood pressure \<90 mmHg

Exclusion Criteria:

* Subjects not in the defined age range
* Participants who have cardiac, respiratory, neurological, and/or metabolic illnesses
* Any known history of renal or hepatic insufficiency/disease
* Pregnancy or breast feeding
* Body mass less than 60 kilograms
* Current smokers, as well as individuals who regularly smoked within the past 3 years
* Individuals with a history of drug abuse within the past 5 years
* Individuals who have an unexplained positive urine drug screen (e.g., some agents cause false-positive results and when agent abstained the drug screen is negative, one example could be an over the counter supplement)
* Currently taking pain modifying medications

Primary outcomes:
measure: Change in core body temperature
timeFrame: Within 30 minutes before exposure to warm environmental conditions, throughout 60 minutes of exercise, and during the 30 minute recovery period.
Secondary outcomes:
measure: Change in skin temperature
timeFrame: Within 30 minutes before exposure to warm environmental conditions, throughout 60 minutes of exercise, and during the 30 minute recovery period.
measure: Change in heart rate
timeFrame: Within 30 minutes before exposure to warm environmental conditions, throughout 60 minutes of exercise, and during the 30 minute recovery period.
measure: Change in whole body sweat rate
timeFrame: Within 30 minutes before exposure to warm environmental conditions and immediately after the 30 minute recovery period.
measure: Change in blood pressure
timeFrame: Within 30 minutes before exposure to warm environmental conditions, throughout 60 minutes of exercise, and during the 30 minute recovery period.
measure: Perceptual questionnaire on how hot one feels
timeFrame: These values will be obtained throughout the 60 minutes of exercise and during the 30 minute recovery period
measure: Perceptual questionnaire on how hard one feels they are exercising
timeFrame: These values will be obtained throughout the 60 minutes of exercise and during the 30 minute recovery period
Other outcomes:
Locations:
city: Dallas
country: United States
facility: University of Texas Southwestern Medical Center
state: Texas
Study officials:
References: