Table 2.
The summary of reported adverse events in the included studies.
| Adverse events | N | Intervention |
Control |
RR [95%CI] | Heterogeneity |
|||
|---|---|---|---|---|---|---|---|---|
| Events | Total | Events | Total | I2 | P | |||
| Nausea and vomiting | 8 | 26 | 398 | 29 | 263 | 0.56 (0.32, 0.98) | 0.0% | 0.834 |
| Dry mouth | 3 | 5 | 90 | 37 | 90 | 0.08 (0.03, 0.23) | 10.5% | 0.327 |
| Dysphoria | 3 | 9 | 80 | 21 | 80 | 0.36 (0.15, 0.84) | 44.5% | 0.165 |
| Pain | 2 | 156 | 262 | 55 | 88 | 0.88 (0.54, 1.45) | 0.0% | 0.610 |
| Bradycardia | 3 | 20 | 297 | 11 | 123 | 0.74 (0.34, 1.58) | 0.0% | 0.469 |
| Respiratory depression | 1 | 0 | 30 | 1 | 30 | – | – | – |
| Fever | 1 | 3 | 242 | 8 | 68 | 0.09 (0.02, 0.37) | – | – |
| Muscle spasm | 1 | 0 | 242 | 4 | 68 | – | – | – |
| Skin rash | 1 | 1 | 30 | 1 | 30 | – | – | – |
| Shivering | 1 | 4 | 30 | 5 | 30 | 0.77 (0.19, 3.20) | – | – |
| Total | 12 | 251 | 1797 | 185 | 945 | 0.44 (0.24, 0.82) | 74.9% | <0.001 |
Abbreviation: N = number; RR = relative risk.