【藥品性質提示】 根據 2019 AGS Beers Criteria，本藥品為【潛在不適當用藥 (PIM)】，不建議用於有骨折風險之老年人(除非用於癲癇、調節情緒)。 #特殊劑型：不建議磨粉、管灌藥品 #最小單位貼紙

治療癲癇、雙極症、預防偏頭痛 Bipolar disorder (acute mania), Focal (partial) onset and generalized onset seizures, Migraine prophylaxis

Anticonvulsants
Valproate sodium is an antiepileptic agent with unknown therapeutic mechanism of action, although, it is believed to exert its effect by increasing the concentrations of gamma-aminobutyric acid (GABA) in the brain.

Distribution
1. Vd: 11 L/1.73 m²
2. Protein binding: approximately 10% unbound at 40 mcg/mL and 18.5% unbound at 130 mcg/mL, concentration dependent
Metabolism
Hepatic; glucuronosyltransferase; over 40% by mitochondrial beta-oxidation, glucuronidation
Excretion
1. Renal: 30% to 50% as glucuronide conjugate, less than 3% unchanged
2. Dialyzable: yes (hemodialysis), about 20%
Elimination Half Life
1. 16 h +/- 3 h
2. Children (greater than 2 mo): 7 h to 13 h
3. Neonates (less than 10 days): 10 h to 67 h
4. Liver impairment: increased from 12 h to 18 h

1. Hypersensitivity to valproic acid
2. Hepatic or renal function impairment
3. Blood dyscrasias

D

Safe

Nausea, vomiting, GI irritation, drowsiness, ataxia, transient alopecia, liver dysfunction

Bipolar disorder, rapid symtom control:
1. Initial: 20 to 30 mg/kg/day. After 2 to 3 days, adjust dose upward or downward to reach desired clinical effect and therapeutic serum concentration.(generally occur with daily doses of 1.5 to 2.5 g)
2. Maximum recommended dosage: 60mg/kg/day
Focal (partial) onset seizures and generalized onset seizures:
1. Initial: 10-15mg/kg/day, increased by 5-10mg/kg daily at one week intervals until seizures are controlled
2. Maximum recommended dosage: 60mg/kg/day
Migraine prophylaxis:
1. Initial: 500 mg once daily; increase dose gradually based on response and tolerability in increments of 250 mg/day at intervals >3 days up to 1 g/day.
2. Based on clinical experience, some patients require doses up to 1.5 g/day for sufficient response; however, adverse effects are increased

Seizures disorders: (Not recommended for ages <6 years)
1. Initial: 10-15mg/kg/day in 1 to 3 divided doses, increased by 5-10mg/kg daily at one week intervals until seizures are controlled
2. Maintenance: 30 to 60 mg/kg/day in 2 to 3 divided doses
Migraine prophylaxis: (Limited data available, for Children ≥12 years and Adolescents)
Initial 500 mg once daily for 15 days, may increase to 1,000 mg once dailiy; dose should be individualized

1. CrCl ≥10 mL/minute: No dosage adjustment necessary.
2. CrCl <10 mL/minute: No specific dosage adjustment necessary; however, free valproate clearance may be reduced up to ~30%.
3. Hemodialysis: No specific dosage adjustment necessary; At therapeutic concentrations, dialysis decreases valproic acid concentrations by 20%

1. Mild to moderate impairment: Not recommended for use in hepatic disease; clearance is decreased with liver impairment.
2. Severe impairment: Use is contraindicated.