Effects of fixed doses of morphine or lidocaine on the others analgesic potency
| ED50 | 95% Confidence Limits | Shift | |
|---|---|---|---|
| mM | |||
| Lidocaine alone | 2.5 | (2.0, 3.4) | |
| +Morphine 1.5 mM | 1.0 | (0.4, 1.8) | 2.5 |
| +Morphine 3.0 mM | 0.8 | (0.6, 1.1) | 3.1 |
| +Morphine 4.5 mM | 0.7 | (0.5, 0.9) | 3.6 |
| Morphine alone | 6.1 | (4.3, 8.4) | |
| +Lidocaine 0.45 mM | 3.6 | (2.6, 4.5) | 1.7 |
| +Lidocaine 0.9 mM | 1.5 | (0.9, 2.6) | 4.1 |
| +Lidocaine 1.8 mM | 1.3 | (0.6, 1.3) | 4.7 |
ED50 values with 95% confidence limits were determined from at least three doss of topical lidocaine alone or with the indicated morphine concentration, or with topical morphine alone or with the indicated concentration of lidocaine.