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In Progress: Phenobarbital and Methylphenobarbital Pathway, Pharmacokinetics/Pharmacodynamics

PA166348361 Last updated January 2026 Caroline F. Thorn
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Drugs & chemicals
0
Genes
0/0
Conditions
23
Reactions
In Progress: Phenobarbital and Methylphenobarbital Pathway, Pharmacokinetics/Pharmacodynamics pathway diagram
In Progress: Phenobarbital and Methylphenobarbital Pathway, Pharmacokinetics/Pharmacodynamics — pathway diagram from PharmGKB / ClinPGx
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Reactions & interactions (23)

  • Activation
    NR1I2 → CYP2B6
  • Activation
    NR1I2 → UGT1A1
  • Activation
    NR1I3 → CYP3A4
  • Activation
    phenobarbital → NR1I2
  • Activation
    phenobarbital → NR1I3
  • Activation
    NR1I3 → UGT1A1
  • Activation
    NR1I2 → CYP3A4
  • Biochemical Reaction
    r-methylphenobarbital → 4-hydroxyphenobarbital
  • Biochemical Reaction
    phenobarbital → phenobarbital n-glucoside
  • Biochemical Reaction
    4-hydroxyphenobarbital → p-hydroxy phenobarbital glucuronide
  • Biochemical Reaction
    primidone → phenobarbital
  • Biochemical Reaction
    primidone → phenylethylmalondiamide
  • Biochemical Reaction
    s-methylphenobarbital → phenobarbital
  • Biochemical Reaction
    phenobarbital → 4-hydroxyphenobarbital
  • Biochemical Reaction
    r-methylphenobarbital → phenobarbital
  • Catalysis
    CYP2C19 → Biochemical Reaction
  • Catalysis
    CYP2B6 → Biochemical Reaction
  • Catalysis
    CYP2C19 → Biochemical Reaction
  • Catalysis
    CYP2E1 → Biochemical Reaction
  • Catalysis
    CYP2C9 → Biochemical Reaction
  • Catalysis
    CYP2B6 → Biochemical Reaction
  • Leads To
    methylphenobarbital → r-methylphenobarbital
  • Leads To
    methylphenobarbital → s-methylphenobarbital

Edit history (3)

  • 2024-08-20 Create
  • 2024-08-30 Update Removed CYP3A and replaced with CYP3A4.
  • 2026-01-27 Update Added methylphenobarbital enantiomer specific metabolism.
In Progress: Phenobarbital and Methylphenobarbital Pathway, Pharmacokinetics/Pharmacodynamics pathway diagram (enlarged)