Table 1. Plasma pharmacokinetic parameters (median [range]) derived from a 2‐compartmental model with first‐order absorption for acetaminophen in foals after a single oral administration at 20 and 40 mg/Kg of body weight.

PK parameter	Units	20 mg/Kg	40 mg/Kg
K01	1/h	1.4 (0.4–2.3)	2.2 (0.7–4.3)
K01_HL	h	1.0 (0.3–1.6)	0.4 (0.2–0.8)
K10	1/h	0.2 (0.1–0.3)	0.2 (0.1–0.3)
K10_HL	h	6.7 (2.1–14)	4.6 (3.3–6.7)
K12	1/h	n/a	0.1 (0.0–0.2)
K21	1/h	n/a	1 (0.0–0.3)
Tmax	h	1.3 (0.5–2.3)	1.5 (0.7–1.9)
Cmax	ug/mL	12 (7.5–18)	14 (12–18)
AUC	h*ug/mL	74 (45.1–100)	130 (77–216)

AUC0‐∞= area under the plasma concentration‐time curve from 0 hours to infinity after dosing; Cmax = maximum concentration; Tmax = time to maximum concentration, K01 = absorption rate constant; K01_HL = half‐life of absorption; K10 = terminal rate constant; K10_HL = half‐life of terminal portion of the curve after oral administration. K12 and K21 are the distribution and redistribution rate constants. N/a = not applicable. PK parameters for 2 horses in the 20 mg/Kg dose were calculated using noncompartmental analysis because no pharmacokinetic model fit their acetaminophen disposition.