Hyperammonemia Associated with Valproic Acid Concentrations

Table 1

VPA levels in plasma, plasma ultrafiltrate, and saliva in children under VPA monotherapy.

Dose (mg/day)	Plasma [VPA] (mg/L)	ult [VPA] (mg/L)	Saliva [VPA] (mg/L)	S/P	ULT/P	PB (%)	Salivary pHs
480	41.5	4.9	1.5	0.036	0.118	88.2	6.88
600	87.5	11.0	3.7	0.042	0.126	87.4	6.92
600	72.7	20.3	6.3	0.087	0.279	72.1	6.89
600	39.7	5.6	1.4	0.035	0.141	85.9	6.79
600	60.8	6.5	3.4	0.056	0.107	89.3	7.11
750	101.9	20.6	7.8	0.077	0.202	79.8	6.98
750	58.4	9.3	3.8	0.065	0.159	84.1	7.01
750	80.9	10.6	4.1	0.051	0.131	86.9	6.99
800	59.4	9.7	2.1	0.035	0.163	83.7	6.73
1000	65.6	9.1	2.8	0.043	0.139	86.1	6.89
1250	116.1	12.4	4.5	0.039	0.107	89.3	6.96
Means				0.051	0.152	84.8	6.92
S.D.				0.018	0.050	5.0	0.10

[VPA]: valproic acid concentration; ult: plasma ultrafiltrate; S/P: saliva/plasma ratio, ULT/P: plasma ultrafiltrate/plasma ratio; PB: protein binding; SD: standard deviation.