Recorded pharmacokinetic data for caffeine
| Study | n | D | Vd(p)ss | Cl | F | t ½ | U/P |
| Vickroy et al 24 | 6 | 3 mg/kg intravenously | 760 | 24 | – | 11.2 | – |
| Greene et al 45 | 4 | 4 mg/kg intravenously | 650 | 24 | – | 18.26 | 3 |
| 4 | 4 mg/kg orally | – | – | 0.39 | 42* | 3 | |
| Chou et al 46 | 2 | 3 mg/kg intravenously | 820 | 39 | – | 15.3 | – |
| 2 | 3 mg/kg intravenously | 780 | 37.8 | – | 14.4 | – | |
| Peck et al 47 | 4 | 2.5 mg/kg intravenously | 1318 | 51 | – | – | – |
| Aramaki et al 13 | 4 | 2.5 mg/kg intravenously | 852 | 42.5† | – | 13.88† | – |
| 4 | 2.5 mg/kg intramuscularly | 834 | – | – | |||
| 4 | 2.5 mg/kg orally | 809 | 1.12† | – | |||
| Schumacher et al 48 | 10 | 500 mg/horse (0.8–1.8 mg/kg) intravenously | 694 | 42.7 | – | 10.18 | – |
| Aramaki et al 49 | 4 | 2.5 mg/kg intravenously | 887 | 40.4 | – | 15.5 | – |
| 5 | 2.5 mg/kg intramuscularly | 965 | 36.6 | – | 18.6 | – | |
| 4 | 2.5 mg/kg orally | 881 | 39 | 1.04 | 16.4 | – | |
| Todi et al 50 | 3 | 2 g/ horse orally | – | – | – | – | 3.16† |
| Kaiser51 | 6 | 4 mg/kg intravenously | 1209 | 71.6 | – | 16.1 | – |
| 6 | 4 mg/kg orally | – | 128.2* | 0.56 | – | – | |
| Machnik et al 21 | 6 | 4 mg/kg intravenously | 1345 | 55 | – | 17.2 | 2 |
*Significant outlier.
†Calculated value.
Cl, clearance in ml/hour x kg; D, dose; F, bioavailability;n, number of animals.t ½, terminal half-life in hours; U/P, urine–plasma concentration ratio in the steady-state or pseudo-steady-state; Vd(p)ss, volume of distribution in ml/kg in the (pseudo)-steady state;