- Molecular NamePrimidone
- SynonymNA
- Weight218.256
- Drugbank_IDDB00794
- ACS_NO125-33-7
- Show 2D model
- LogP (experiment)0.91
- LogP (predicted, AB/LogP v2.0)0.55
- pkaN/A
- LogD (pH=7, predicted)0.55
- Solubility (experiment)500 mg/L
- LogS (predicted, ACD/Labs)(ph=7)-2.21
- LogSw (predicted, AB/LogsW2.0)2.13
- Sw (mg/ml) (predicted, ACD/Labs)1.34
- No.of HBond Donors2
- No.of HBond Acceptors4
- No.of Rotatable Bonds2
- TPSA58.2
- StatusFDA approved
- AdministrationN/A
- PharmacologyAn anticonvulsant of the pyrimidinedione. Primidone was once a mainstay anticonvulsant in the treatment of partial and generalized seizures and was the treatment of choice for secondarily generalized seizures originating in the temporal lobes, especially when combined with phenytoin, but by the early 1980s, carbamazepine had surpassed it in popularity due to the latter's lower incidence of sedation.
- Absorption_value95.0
- Absorption (description)N/A
- Caco_2N/A
- Bioavailability92.0
- Protein binding20.0
- Volume of distribution (VD)0.6 L/kg
- Blood/Plasma Partitioning ratio (D_blood)N/A
- MetabollsmPrimidone converts to phenobarbital and PEMA; it is still unknown which exact cytochrome P450 enzymes are responsible. The phenobarbital, in turn, is metabolized to p-hydroxyphenobarbital.
- Half lifeprimidone about 10 to 15 h, phenobarbital 50 to 150 h, PEMA 24 to 48 h.
- ExcretionRenal
- Urinary ExcretionN/A
- CleranceN/A
- ToxicityThe most frequent occurring early side effects are ataxia and vertigo. These tend to disappear with continued therapy, or with reduction of initial dosage. Occasionally, the following have been reported: nausea, anorexia, vomiting, fatigue, hyperirritability, emotional disturbances, sexual impotency, diplopia, nystagmus, drowsiness, and morbilliform skin eruptions.
- LD50 (rat)N/A
- LD50 (mouse)N/A