Healthy
Conditions
Brief summary
In previous clinical studies of post-surgical pain the investigators found that nalbuphine (Nubain), a narcotic pain killer, relieves pain more effectively when combined with low-dose naloxone (Narcan), a drug that is used to treat narcotic overdose. This finding was particularly true in men. The purpose of this study is to find out if nalbuphine combined with naloxone is more effective in relieving experimentally produced pain than either drug alone. A second reason for this study is to find out if study medications work more effectively in women or in men. Subjects will come to the University of California at San Francisco (UCSF) Clinical Research Center (CRC) for 4 study visits. The first visit will be a 2-hour screening to assess the subject for study eligibility. During the other three visits, the investigators will use a thermal stimulating device to produce temporary, non-injurious skin sensitivity that subjects will feel as painful. Changes in pain will be measured following the intravenous (i.v.) administration of study drugs. Three drug combinations will be administered, a different one each visit: 1) nalbuphine 5 mg and naloxone 0.4 mg , 2) naloxone 0.4 mg and saline (an inactive solution), nalbuphine 5 mg and saline. These drug combinations will be administered in random order; all subjects will receive all three combinations.
Interventions
single dose administered intravenously
DRUGnalbuphine plus saline
single dose administered intravenously
DRUGnaloxone plus saline
single dose administered intravenously
Sponsors
University of California, San Francisco
Study design
Allocation
NON_RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* Age 18 - 40 * In stable health * Speak, read, understand English language * If female, must be non-lactating and not pregnant
Exclusion criteria
* Heat pain detection thresholds above 47 ºC/116.6 ºF * Inability to develop secondary hyperalgesia from the heat and capsaicin stimulation performed at the screening visit * Serious psychiatric psychopathology (psychotic disorder, substance abuse) * Tattoos in the area of measurements * Allergy to study drugs (nalbuphine, naloxone, or capsaicin) * Current or recent use opioids
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Skin Sensitivity as Measured by a Visual Analog Scale | Prior to drug administration and 20 minutes, 70 minutes and 2 hours after each drug administration | Participants would have been asked to rate the level of pain on a scale from 0 (no pain) to 10 (worst pain imaginable). |
Countries
United States
Participant flow
Recruitment details
Recruitment details unavailable due to death of investigator
Pre-assignment details
Pre-assignment details unavailable due to death of investigator
Participants by arm
| Arm | Count |
|---|---|
| Men-all Three Combinations the investigators will use a thermal stimulating device to produce temporary, non-injurious skin sensitivity that subjects will feel as painful. Changes in pain will be measured following the intravenous (i.v.) administration of study drugs. Three drug combinations will be administered, a different one each visit: 1) nalbuphine 5 mg and naloxone 0.4 mg , 2) naloxone 0.4 mg and saline (an inactive solution), nalbuphine 5 mg and saline. These drug combinations will be administered in random order; all subjects will receive all three combinations. | 3 |
| Total | 3 |
Baseline characteristics
| Characteristic | Men-all Three Combinations |
|---|---|
| Age, Customized Unknown | 3 Participants |
| Region of Enrollment United States | 3 participants |
| Sex: Female, Male Female | 0 Participants |
| Sex: Female, Male Male | 3 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 0 |
| serious Total, serious adverse events | 0 / 0 |
Outcome results
Primary
Change in Skin Sensitivity as Measured by a Visual Analog Scale
Participants would have been asked to rate the level of pain on a scale from 0 (no pain) to 10 (worst pain imaginable).
Time frame: Prior to drug administration and 20 minutes, 70 minutes and 2 hours after each drug administration
Population: The planned model of skin irritation could not be reproduced on 3 enrolled participants, thus the investigator did not obtain outcome data.