Table 5.
Main pharmacokinetic parameters of gabapentin in dogs, cats, and horses expressed as mean (±SD) or median (range min–max).
| Dose and Formulation | Bioavaila-Bility (%) | CMAX (µg/mL) |
TMAX
(h) |
Terminal Half-Life (h) |
AUC (µg × h/mL) |
CL (ml/min/kg) |
VD (L/kg) |
KEL (1/h) | Effective Dose (Supposed or Proven) | N. of Subjects | Reference |
|---|---|---|---|---|---|---|---|---|---|---|---|
| DOG | |||||||||||
| 10 mg/kg orally (po)-tablets | 9.68 (5.32–10.90) | 1.50 (0.75–2.00) | 3.35 (2.63–3.68) | 49.5 (39.77–63.02) | 3.49 (2.97–4.26) |
0.94 (0.85–1.26) |
- | 10–20 mg/kg every 8 h | 6 | [96] | |
| 20 mg/kg po-tablets | 12.95 (10.70–18.20) | 1.75 (1.00–2.00) | 3.39 (3.07–3.91) | 83.01 (60–151.24) | 3.97 (2.65–5.56) |
1.20 (0.83–1.48) |
- | ||||
| 50 mg/kg po | 80 | 56.3 | 1.1 | 2.2 | 242 | - | - | - | 1 | [25] | |
| 50 mg/kg iv | - | - | - | 2.9 | 367 | 2.27 | 0.16 | - | |||
| CAT | |||||||||||
| 4 mg/kg iv-bolus | 47.39 ± 5.10 (30.21–62.38) | - | - | - | 3.02 ± 0.18 (2.45–3.46) | 0.65 ± 0.01 (0.60–0.70) | 0.035 ± 0.004 (0.026–0.049) | 6 | [94] | ||
| 10 mg/kg po-capsules | 88.7 ± 11.1 (49.6–118.3) | 7.98 ± 1.05 (4.64–10.55) |
1.66 ± 0.3 (1.0–2.92) | 2.95 ± 0.3 | - | 2.99 ± 0.22 (2.45–3.46) | - | 0.004 ± 0.000 (0.003–0.003) | |||
| 5 mg/kg iv-bolus | - | - | - | 3.78 (3.12–4-47) | 32.01 (24.61–42.38) | 2.67 (1.99–3.31) |
0.804 (0.643–1.05) | 1.21 (0.87–1.67) | 8 | [95] | |
| 10 mg/kg po-capsules-single dose | 94.8 (82.5–122.8) | 12.42 (8.31–18.35) | 1.05 (0.74–2.11) | 3.53 (2.96–4.78) | 73.68 (55.71–107.19) | - | - | 0.20 (0.14–0.23) | 8 mg/kg every 6 h | ||
| 10 mg/kg po-capsules-repeated doses | - | 14.78 (9.70–18.41) | 0.77 (0.58–1.64) | 3.90 (3.12–4.51) | 77.25 (66.26–121.06) | - | - | 0.18 (0.15–0.22) | |||
| 20 mg/kg po-capsules single dose |
- | 24.2 (18.4–27.1) | 1.5 (1–2) | 4.1 ± 0.5 | 158 (144–172) | - | - | 0.17 (0.14–0.2) | 5 | [104] | |
| HORSE | |||||||||||
| 5 mg/kg po | - | 0.27 ± 0.02 | 1.41 ± 0.1 | 3.40 ± 0.48 | 1.78 ± 0.26 | 0.05± 0.01 | - | - | 4 | [105] | |
| 20 mg/kg iv | 73.0 (66.2–76.3) | - | 8.53 (7.06–13.3) | 216.6 (195.1–267.5) | 1.61 (1.28–1.68) |
0.81 (0.66–0.90) |
- | 6 | [92] | ||
| 20 mg/kg po | 16.2 ± 2.8 | 3.75 (1.89–5.76) | 1.00 (0.75–2.00) | 7.73 (6.70–11.93) | 38.8 (22.9–61.6) | 1.45 (1.21–1.6) | - | 0.09 (0.06–0.1) | |||
| 10 mg/kg nasogastric po-water dissolved tablets | - | 1.6 (1.5–2.4) | 2.6 (2.0–3.3) | 5.5 (3.9–11.3) | 31 (27–35) | - | - | 0.6 (0.478–0.760) |
10 mg/kg every 8 h or 20 mg/kg every 12 h or 80 mg/kg every 24 h | 3 | [89] |
| 20 mg/kg nasogastric po-water dissolved tablets | - | 3.2 (3.2–3.5) | 2.7 (2.5–2.9) | 7.6 (6.1–8.2) | 49 (48–61) | - | - | 0.9 (0.467–1.09) | 3 | ||
| 60 mg/kg nasogastric po-water dissolved tablets | - | 4.0 (2.8–8.4) | 1.9 (1.5–2.4) | 7.2 (2.1–13.8) | 79 (52–150) | - | - | 1.5 (0.747–2.07) | 6 | ||
| 80 mg/kg nasogastric po-water dissolved tablets | - | 6.7 (3.2–10.0) | 2.2 (1.0–2.7) | 6.0 (4.1–11.9) | 110 (69–180) | - | - | 0.8 (0.506–2.818) | 6 | ||
| 120 mg/kg nasogastric po-water dissolved tablets | - | 8.4 (4.8–15) | 1.8 (1.4–3.7) | 7.9 (13.3–15.7) | 150 (120–220) | - | - | 0.8 (0.792–1.81) | 6 | ||
| 160 mg/kg nasogastric po-water dissolved tablets | - | 8.5 (5.0–11.0) | 1.4 (1.0–2.6) | 11.5 (4.1–13.9) | 160 (110–230) | - | - | 2.3 (0.522–3.492) | 6 | ||
| 40 mg/kg po-tablets mixed with corn oil and applesauce or molasses every 12 h for 14 days | - | 7.6 (6.2–11) first dose 8 (6.6–11) last dose |
1 (1–2) first dose 0.4 (0–8) last dose |
11 (6–30) first dose 15 (13–29) last dose |
146 (104–400) after last dose |
- | - | - | 120 mg/kg every 12 h | 6 | [90] |
| 120 mg/kg po-tablets mixed with corn oil and applesauce or molasses every 12 h for 14 days | - | 9.9 (6.1–27) first dose 22 (14–33) last dose |
1 (1–2) first dose 0.0 (0.0–0.3) last dose |
7.2 (6.2–19) first dose 20 (12–22) last dose |
550 (270–650 after last dose) |
- | - | - | |||