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MUSCULO-SKELETAL SYSTEM › MUSCLE RELAXANTS › MUSCLE RELAXANTS, CENTRALLY ACTING AGENTS › Carbamic acid esters
phenprobamate
M03BA01
Forms & Strengths
- Oral tablets: 400 mg
- Combination oral preparations (varies by region)
Adult Dosing
- 400 mg to 800 mg orally 3 times daily
- Maximum daily dose generally up to 2400 mg
Pediatric Dosing
- Safety and efficacy not established in pediatric patients
- Not recommended for use in children
Indications
- Symptomatic relief of painful muscle spasms associated with musculoskeletal conditions
Mechanism of Action
- Central nervous system (CNS) depressant
- Acts at the spinal cord and subcortical levels of the brain to inhibit polysynaptic reflexes
- Produces skeletal muscle relaxation and mild sedative effects
Contraindications
- Hypersensitivity to phenprobamate or structurally related compounds (e.g., meprobamate)
- Severe hepatic impairment
- Acute intermittent porphyria
- Myasthenia gravis
- Severe respiratory depression
Adverse Reactions
- Drowsiness and sedation
- Dizziness and vertigo
- Nausea and gastrointestinal upset
- Hypotension
- Allergic skin reactions
- Paradoxical CNS stimulation (rare)
Drug Interactions
- Enhancement of CNS depression with alcohol, barbiturates, opioids, and sedatives
- Potential potentiation of skeletal muscle relaxants
- Increased risk of drowsiness with antihistamines and psychotropic medications
Curated Content: Needs Vetting Before Put to Clinical Use