General information:
Substance group: Antiepileptic drugs ATC: N03AA03
Trade names: Liskantin®, Mylepsinum®, Primidon-*®
doses available: tablets 250 mg, oral suspension 25 mg/mL
Reference ranges:
Primidon 3 – 12 mg/L
Phenobarbital 10 – 30 mg/L
Toxic plasma mirrors: 25 mg/L (Primidon), 50 mg/L (phenobarbital)
Sampling:
Material: Serum (Monovette brown) Minimum volume for analysis: 500µL
Recommendation: trough level (directly before the next intake)
Requirement (internal): about …. Requirement (external):
Analysis:
Test principle: High-performance liquid chromatography with UV detection (HPLC-UV)
Liquid-liquid extraction with ether, chromatographic separation, absorption measurement
Analysis system: HPLC
Findings communication: on the day of submission, via LIMS
Pharmacokinetics:
T1⁄2 : Monotherapy: 15.2 h (8.9 – 22.4 h) (combination: 8.3 h)
Tmax: 0,5 – 9 h (PB: 2 – 4 d; PEMA: 7 – 8 h)
Bioavailability: > 90%
Protein binding: about 50%
Clearance: 30 mL/min
Excretion: urine: 75.5% (children: 92%)
Metabolism: hepatic
Therapeutic width: 3 – 8 mg/L
Toxic:
Distribution volume: 0.54 L/kg
Time to steady state:
Indication:
Level 2: TDM recommended
TDM at least every 3-6 months or more frequently in case of dose titration, suspected non-adherence, dose alterations, changes in comedication, adverse drug effects, intoxication, pregnancy, change in kidney function or simultaneous use of liverenzyme inducing/inhibiting drugs.
DrugBank: https://go.drugbank.com/drugs/DB00794