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Phenobarbital

    Brands

    DEA Class;  Rx

    Common Brand Names; Luminal

    • Anticonvulsants, Barbiturates

    Oral and parenteral anticonvulsant and sedative-hypnotic; longest acting barbiturate; effective in all seizure disorders except absence (petit mal); also used for neonatal withdrawal syndrome; close monitoring for emerging or worsening suicidal thoughts/behavior or depression is recommended.

    Typically used after benzodiazepines and phenytoin fail to abort status epilepticus

    All types of seizure disorders, including partial, tonic-clonic, and myoclonic seizures

    For the maintenance treatment of all types of seizures, including but not limited to partial seizures, myoclonic seizures, tonic-clonic seizures, or neonatal seizures not responding to other anticonvulsants.

    For the short-term treatment of insomnia.
    For procedural sedation and relief of preoperative anxiety.
    For sedation maintenance, to relieve anxiety, tension, and apprehension.
    For the treatment of hyperbilirubinemia.
    For neonatal abstinence syndrome.

    Hypersensitivity

    Porphyria

    Intra-arterial or subcutaneous administration

    Severe hepatic impairment

    Dyspnea or airway obstruction

    History of sedative hyponotic addiction

    Nephritic patients (large doses)

    Pregnancy/lactation

    IV

    • Respiratory depression

    Common

    • Ataxia

    • Dizziness

    • Drowsiness

    • Dysarthria

    • Fatigue

    • Headache

    • Irritability

    • Nystagmus

    • Paresthesia restlessness

    • Vertigo

    • Geriatric patients: Excitement, confusion, depression

    • Pediatric patients: Paradoxical excitement/hyperactivity

    Less Common

    • Mental dullness

    • Constipation

    • Diarrhea

    • Nausea

    • Vomiting

    • Megaloblastic (folate-deficiency) anemia

    Uncommon

    • Rash

    • Hypocalcemia

    • Hepatotoxicity

    Rare

    • Stevens-Johnson syndrome

    • Rickets

    • Osteomalacia

    Commercial injection is highly alkaline and may cause tissue necrosis if given SC or if it extravasates (if happens, treat with application of moist heat and injection of 0.5% procaine)

    May render oral contraceptives ineffective

    Paradoxical responses may occur, especially in pediatric patients and patients experiencing acute or chronic pain

    May cause CNS depression, causing physical and mental impairment; caution patient about performing tasks that require mental alertness

    May cause respiratory depression, especially with intravenous administration; use caution in patients with respiratory disease and status asthmaticus

    Withdraw therapy gradually; abrupt discontinuation, may increase seizure frequency

    Use caution in patients with severe anemia, patients experiencing depression, cardiac disease, hemodynamically unstable patients, hyperthyroidism, renal impairment, hypoadrenalism, and in patients with diabetes

    May mask important symptoms when used in patients with acute or chronic pain; use caution

    Pregnancy category: D

    Lactation: Do not nurse

    Adults

    Specific maximum dosage information not available; individualize dosage based on monitoring of serum phenobarbital concentrations and clinical parameters. 200 mg/day PO is a general estimation for outpatient chronic use.

    Geriatric

    Specific maximum dosage information not available; individualize dosage based on monitoring of serum phenobarbital concentrations and clinical parameters. 200 mg/day PO is a general estimation for outpatient chronic use.

    Adolescents

    Specific maximum dosage information not available; individualize dosage based on monitoring of serum phenobarbital concentrations and clinical parameters. For status epilepticus, single doses do not usually exceed 20 mg/kg IV (Max: 1,000 mg/dose); for anticonvulsant maintenance treatment, doses above 6 mg/kg/day are not usually necessary.

    Children

    Specific maximum dosage information not available; individualize dosage based on monitoring of serum phenobarbital concentrations and clinical parameters. For status epilepticus, single doses do not usually exceed 20 mg/kg IV (Max: 1,000 mg/dose); for anticonvulsant maintenance treatment, doses above 8 (7 years and older) to 10 mg/kg/day (6 years and younger) are not usually necessary.

    Infants

    Specific maximum dosage information not available; individualize dosage based on monitoring of serum phenobarbital concentrations and clinical parameters. For status epilepticus, single doses do not usually exceed 20 mg/kg IV; for anticonvulsant maintenance treatment, doses above 10 mg/kg/day are not usually necessary.

    Neonates

    Specific maximum dosage information not available; individualize dosage based on monitoring of serum phenobarbital concentrations and clinical parameters. For status epilepticus, single doses do not usually exceed 20 mg/kg IV; for anticonvulsant maintenance treatment, doses above 5 mg/kg/day are not usually necessary.

    Phenobarbital

    tablet: Schedule IV

    • 15mg

    • 16.2mg

    • 30mg

    • 32.4mg

    • 60mg

    • 64.8mg

    • 97.2

    • 100mg

    elixir: Schedule IV

    • 20mg/5mL

    injectable solution: Schedule IV

    • 65mg/mL

    • 130mg/mL