Study on the Development of Opioid Induced Hyperalgesia (OIH) After Exposure to Alfentanil (0813)

Johns Hopkins University

Status

Completed

Conditions

Hyperalgesia

Treatments

Drug: Diphenhydramine

Drug: Alfentanil

Study type

Interventional

Funder types

Other

NIH

Identifiers

NCT00991809

1K24DA023186 (U.S. NIH Grant/Contract)

NA_00022154

Details and patient eligibility

About

The purpose of this study was to follow a person's response to experimental pain after multiple consecutive exposures to alfentanil or diphenhydramine to see if the person can tolerate the pain more, less, or the same at the end of the study.

Full description

This project investigates the phenomenon of opioid-induced hyperalgesia (OIH). Opioid analgesics, in addition to their therapeutic anti-nociceptive effects, under some conditions produce pro-nociceptive effects. This phenomenon of pain or pain sensitivity being increased by prior opioid administration is called opioid-induced hyperalgesia. It is thought to be relevant both to pain management complications and to complications of opioid dependence and its treatment. This study investigated the time-course of opioid-induced hyperalgesia development in healthy normal volunteers (N=12 completers), using a series of acute alfentanil administrations (15 mg/kg mg intramuscular (IM) per day) spaced at 3-4 day intervals, with testing for pain tolerance using the cold pressor test (CPT), and mechanical quantitative sensory testing (MQST) each administered repeatedly over time within each testing day. The goal was to determine the time course of OIH development following acute opioid administration, and to assess whether this changes over repeated acute opioid administrations.

Enrollment

22 patients

Sex

Male

Ages

18 to 55 years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

Age 18-55
No active medical conditions
BMI between 20-30
Able and willing to perform/tolerate pain procedures
Able to communicate in English

Exclusion criteria

Lifetime substance use disorder, except for alcohol abuse/dependence in remission
Use of opiates in last 3 months
Ongoing marijuana use
Acute or chronic pain
Neurologic or psychiatric condition known to influence cold pressor testing (peripheral neuropathy, major depression, or schizophrenia)
Current use of prescribed or over the counter pain medications
Previous adverse reaction to opiate medications or diphenhydramine
Use of tobacco or caffeine on study days