Table 1. CPM studies reporting pharmacological blockade of endogenous opioids.
| Author | n | Pain outcome | Opioid antagonist | Route of administration | Effect on inhibition |
|---|---|---|---|---|---|
| Edwards et al. (2004) | 6 | TS, HPT | Naloxone | i.m. (6 mg/kg) | No effect |
| Peters et al. (1992) | 46a,b | NFR-RIII | Naloxone | i.v. (0.8 mg, 2 mL) | No effect |
| Pertovaara et al. (1982) | 12 | CT, HT | Naloxone | i.v. (2 mg) | Reduced |
| Sprenger et al. (2011) | 22a | HP | Naloxone | i.v. (0.15 mg/kg bolus, 0.2 mg/kg infusion) | No effect |
| Willer et al. (1990) | 9 | NFR-RIII | Naloxone | i.v. (0.4 mg, 4 mL) | Reduced |
CT cold thresholds, HT heat thresholds, HPT heat pain threshold, HP 47.5 °C heat pulse, NFR-RIII nociceptive flexion reflex threshold, TS temporal summation of heat pain, i.v. intravenous, i.m. intramuscular
a
Males only
b
Chronic pin patients