Table 3.
Main results in gabapentin trials
| Efficacy | % with | ||||
|---|---|---|---|---|---|
| Subgroup | Number of patients | Relative benefit (95% CI) | NNT (95% CI) | Placebo | Gabapentin |
| Lack of efficacy withdrawal | |||||
| All | 1425 | 0.41 (0.19, 0.87) | −56 (−510, −30) | 3 | 1 |
| PEE | 639 | 0.41 (0.14, 1.2) | −55 (140, −23) | 3 | 2 |
| NEE | 786 | 0.40 (0.14, 1.1) | −55 (430, −26) | 3 | 1 |
| 1800 mg | 287 | 0.98 (0.21, 4.5) | 250 (25, −31) | 2 | 3 |
| 2400 mg | 644 | 0.30 (0.09, 1.0) | −44 (3000, −22) | 3 | 1 |
| 3600 mg | 494 | 0.33 (0.09, 1.2) | −41 (360, −19) | 4 | 1 |
| Harm | |||||
|---|---|---|---|---|---|
| % with | |||||
| Subgroup | Number of patients | Relative risk (95% CI) | NNH (95% CI) | Placebo | Gabapentin |
| Adverse event withdrawal | |||||
| All | 1546 | 1.4 (1.1, 1.9) | 26 (14, 140) | 9 | 13 |
| PEE | 639 | 1.4 (0.88, 2.1) | 31 (12, −47) | 12 | 15 |
| NEE | 907 | 1.5 (1.0, 2.3) | 27 (13, −2700) | 8 | 11 |
| 1800 mg | 408 | 1.8 (0.82, 3.8) | 21 (10, −810) | 5 | 10 |
| 2400 mg | 644 | 1.4 (0.91, 2.0) | 25 (11, −72) | 12 | 16 |
| 3600 mg | 494 | 1.4 (0.85, 2.4) | 27 (11, −57) | 9 | 12 |
| Somnolence | |||||
| All | 1526 | 3.4 (2.5, 4.7) | 6.4 (5.3, 8.1) | 6 | 22 |
| PEE | 639 | 2.9 (1.7, 5.0) | 8.8 (6.2, 15) | 6 | 17 |
| NEE | 887 | 3.3 (2.6, 5.4) | 5.2 (4.2, 6.8)a | 7 | 26 |
| 1800 mg | 396 | 2.9 (1.6, 5.4) | 7.2 (4.9, 14) | 7 | 21 |
| 2400 mg | 682 | 3.0 (1.9, 4.8) | 7.1 (5.3, 11) | 7 | 21 |
| 3600 mg | 448 | 4.7 (2.6, 8.5) | 5.1 (3.8, 7.6) | 5 | 25 |
| Dizziness | |||||
| All | 1576 | 3.5 (2.7, 4.9) | 5.3 (4.5, 6.5) | 7 | 26 |
| PEE | 639 | 3.2 (2.1, 4.9) | 4.9 (3.9, 6.9) | 9 | 29 |
| NEE | 937 | 3.8 (2.6, 5.6) | 5.7 (4.6, 7.6) | 6 | 24 |
| 1800 mg | 396 | 4.5 (2.3, 8.7) | 5.0 (3.8, 7.5) | 6 | 26 |
| 2400 mg | 682 | 2.8 (1.9, 4.0) | 5.5 (4.2, 7.9) | 10 | 28 |
| 3600 mg | 498 | 4.3 (2.6, 8.2) | 5.3 (4.0, 7.8) | 5 | 24 |
1800 mg, 2400 mg and 3600 mg refer to the maximum available daily doses of gabapentin. For the analysis of dizziness, the 3600 mg subgroup also contains one trial [45] using 4200 mg gabapentin as the maximum available daily dose. a) P = 0.019 for the comparison PEE vs. NEE.