Intranasal Cocaine and Temperature Regulation During Exercise
- Registration Number
- NCT05809453
- Lead Sponsor
- University of Texas Southwestern Medical Center
- 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.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 27
- 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
- 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
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Hot-Humid Cocaine Participants will complete the trial in environmental conditions 38 degrees Celsius with 40% humidity. Hot-Humid Lidocaine Participants will complete the trial in environmental conditions 38 degrees Celsius with 40% humidity. Hot-Dry Cocaine Participants will complete the trial in environmental conditions 41 degrees Celsius with 15% humidity. Hot-Dry Lidocaine Participants will complete the trial in environmental conditions 41 degrees Celsius with 15% humidity.
- Primary Outcome Measures
Name Time Method Change in Core Temperature Core temperature is measured at baseline and at 60 minutes of heat exposure. Core temperature will be measured either from a temperature sensor pill or from a rectal temperature probe.
- Secondary Outcome Measures
Name Time Method End Skin Temperature Measured at the end of heat exposure, 90 minutes from cocaine/lidocaine administration Skin temperature will be measured from small temperature sensitive electrodes attached to the participant's skin
End Heart Rate Measured at the end of heat exposure, 90 minutes from Cocaine/ lidocaine administration Heart rate will be measured from ECG electrodes attached to the participant
Whole Body Sweat Rate Within 30 minutes before exposure to warm environmental conditions (before cocaine/ lidocaine administration) and immediately after the heat exposure (90 minutes post cocaine/ lidocaine administration) Whole body sweat rate is calculated by subtracting the participants post-heat exposure nude body weight from their pre-heat exposure nude body weight
End Mean Arterial Pressure Measured at the end of heat exposure, 90 minutes from cocaine/ lidocaine administration Systolic and diastolic blood pressure will be measured from a cuff placed on the upper arm.
End Thermal Sensation These values will be obtained at end of the 60 minute heat exposure (90 minutes post cocaine/ lidocaine administration) Subjective assessment of how hot the subject feels.
Title of Scale: Thermal Sensation Scale; Minimum value: -50 "unbearably cold"; Maximum value: 50: "unbearably hot" Scale presents numbers in increments of 5
Trial Locations
- Locations (1)
University of Texas Southwestern Medical Center
🇺🇸Dallas, Texas, United States
University of Texas Southwestern Medical Center🇺🇸Dallas, Texas, United States