Dosing and uses of Mebaral (mephobarbital)
Adult dosage forms and strengths
tablet
- 32mg
- 50mg
- 100mg
Sedation
32-100 mg PO TID/QID; optimum dose is 50 mg PO TID/QId
Epilepsy
400-600 mg PO qDay; start with small dose and gradually increase over 4-5 days until optimum dosage determined
Other Indications & Uses
Anxiety; grand mal, petit mal seizures
Pediatric dosage forms and strengths
tablet
- 32mg
- 50mg
- 100mg
Sedation
16-32 mg PO TID/QId
Epilepsy
< 5 years old: 16-32 mg PO TID/QId
> 5 years old: 32-64 mg PO TID/QId
Mebaral (mephobarbital) adverse (side) effects
Frequency not defined
Common
- Somnolence
Less Common
- Bradycardia, hypotension, hypoventilation
- Agitation, confusion, hyperkinesia, ataxia, CNS depression, nightmares, nervousness
- Constipation, nausea, vomiting
Rare
- Fever
- Headache
- Rash
Warnings
Contraindications
Barbiturate sensitivity, porphyria, liver disease, severe respiratory disease
Cautions
Reduce dose in hepatic/renal impairment
Excreted in breast milk
Pregnancy and lactation
Pregnancy category: d
Lactation: excreted in breast milk; use caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Mebaral (mephobarbital)
Half-Life: >30 hr
Onset: 30-60 min
Duration: 10-16 hr
Bioavailability: 50%
Metabolism: N-demethylation, then glucuronate or sulfate conjugation
Metabolites: phenobarbitaL
Excretion: urine
Enzymes induced: CYP1A2, CYP2C9/10, CYP3A4
Mechanism of action
Depress cortical & cerebellar function