Dosing and uses of Meprobamate
Adult dosage forms and strengths
tablet: Schedule IV
- 200mg
- 400mg
Anxiety
1200-1600 mg/day PO divided q6-8hr; not to exceed 2.4 g/day
Preoperative Sedation
400 mg PO before the procedure
Renal Impairment
CrCl 10-50 mL/min: Change frequency of administration to every 9-12hr
CrCl <10 mL/min: Change frequency of administration to 12-18hr
Hepatic Impairment
Use caution
Pediatric dosage forms and strengths
tablet: Schedule IV
- 200mg
- 400mg
Anxiety
<6 years old: Not recommended
6-12 years old: 100-200 mg PO q8-12hr
>12 years old: 1200-1600 mg/day PO divided q8-12hr; not to exceed 2.4 g/day
Preoperative Sedation
200 mg PO prior to procedure
Geriatric dosage forms and strengths
Not drug of choice in elderly because of potential physical and psychological dependence
Use lowest effective dose to avoid oversedation
Anxiety
Lower initial dose; adjust more gradually; 200 mg PO q8-12hr
Meprobamate adverse (side) effects
Frequency not defined
Common
- Abnormal ECG, palpitations, tachyarrhythmia
- Asthenia, ataxia, dizziness, EEG abnormality, euphoria, fast, excitement, paradoxical, headache, paresthesia, slurred speech, somnolence, vertigo
- Hives, maculopapular eruption, erythematous
- Diarrhea, nausea, vomiting
- Disorder of accommodation (ocular)
Serious
- Cardiac dysrhythmia, hypotension crisis, syncope
- Bullous dermatosis (rare), Stevens-Johnson syndrome (rare)
- Agranulocytosis, aplastic anemia, leukopenia
- Anaphylaxis (rare)
Warnings
Contraindications
Hypersensitivity, allergy to related drugs (eg, carisoprodol)
History of porphyria
Cautions
Hypersensitivity may occur
May impair physical or mental abilities due to CNS depression
Secreted into breast milk; avoid during breastfeeding
Caution in patientw with depression or suicidal tendencies
Caution in hepatic/renal impairment or seizure disorder
Pregnancy and lactation
Pregnancy category: d
Lactation: secreted into breast milk at 2-4x plasma concentration; avoid
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 Meprobamate
Mechanism of action
Carbamate derivative; inhibitory effects in thalamus, limbic system; may inhibit multineural spinal reflexes
Mild sedative, anticonvulsant, muscular relaxant effects
Pharmacokinetics
Absorption: well-absorbed from GI tract
Half-Life: 6-16 hr
Onset: <1 hr
Peak plasma time: 1-3hr
Peak plasma concentration: 5-30 mcg/mL (400 mg dose)
Protein Bound: 20%
Metabolism: Liver
Metabolites: Inactive
Excretion: Urine (8-20%); feces (10%)