Answer
Phenytoin sodium shows non-linear pharmacokinetics because its hepatic hydroxylation enzyme system is saturable, so small dose increases can cause very substantial serum-level increases near the upper therapeutic range.
Sources for this answer
- Phenytoin Sodium Flynn Hard Capsules 25mgFlynn Pharma Ltd · emc · SmPC §5.2 Pharmacokinetic properties · Version 18Document updated
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