Phenobarbitone Sodium inj

Indications

Phenobarbitone Sodium inj is used for: Status epilepticus, Partial seizures, Sedation, Generalised tonic-clonic seizures, Hypnotic, Preoperative sedation

Adult Dose

Parenteral Status epilepticus ; Emergency management of acute seizures Adult: As phenobarbital Na: 200-600 mg. OR 15-18 mg/kg IV loading dose infused at 25-60 mg/min; prepare to support ventilation; may repeat in 20-minute intervals PRN; not to exceed 30 mg/kg As a hypnotic Adult: 100-320 mg. Do not admin for >2 wk for the treatment of insomnia. Intramuscular Preoperative sedation Adult: As phenobarbital Na: 100-200 mg 60-90 min pre-op. Hepatic impairment: Reduce dose. Severe: Contraindicated.

Child Dose

Parenteral Status epilepticus ; Emergency management of acute seizures Child: As phenobarbital Na: 100-400 mg. OR Infants and children: 15-20 mg/kg IV infused at a rate not to exceed 2 mg/kg/min; not to exceed 1000 mg/dose <60 kg: IV rate at <30 mg/min May repeat with 5-10 mg/kg bolus dose after 15-30 min PRN; not to exceed cumulative dose of 40 mg/kg Seizures Neonates (<28 days): 3-5 mg/kg/day IV/PO in 1-2 divided doses Infants: 5-6 mg/kg/day in 1-2 divided doses 1-5 years: 6-8 mg/kg/day in 1-2 divided doses 6-12 years: 4-6 mg/kg/day in 1-2 divided doses >12 years: 1-3 mg/kg/day in 1-2 divided doses, OR 50-100 mg BID/TID Intramuscular Preoperative sedation Child: As phenobarbital Na: 16-100 mg 60-90 min pre-op. Intravenous Preoperative sedation Child: 1-3 mg/kg pre-op.

Renal Dose

Renal impairment: Reduce dose. Severe: Contraindicated.

Administration

Reconstitution: Dilute w/ most IV infusion soln (e.g. NaCl 0.45% or 0.9%, lactated Ringer's, dextrose 5%, Ringer's). IV Administration Slow injection at <60 mg/min May be given IM into large muscle

Contra Indications

Severe renal and hepatic disorders. Severe respiratory depression, dyspnoea or airway obstruction; porphyria. Pregnancy.

Precautions

Patient w/ history or sedative/hypnotic addiction; resp disease, depression or suicidal tendencies, hypoadrenalism. Avoid abrupt withdrawal. Mild to moderate renal and hepatic impairment. Elderly or debilitated patient, childn. Pregnancy and lactation. Patient Counselling May impair ability to drive or operate machinery. Monitoring Parameters Monitor CBC, LFTs, mental status and seizure activity. Lactation: Do not nurse

Pregnancy-Lactation

Interactions

May enhance the hepatotoxic potential of paracetemaol overdoses. May decrease levels/effects of various CYP isoenzyme substrates e.g. teniposide, methotrexate, antipsychotics, beta-blockers, calcium-channel blockers, other anticonvulsants, chloramphenicol, cimetidine, corticosteroids, ciclosporin, doxycycline, oestrogens, felbamate, griseofulvin, tacrolimus, furosemide, methadone, oral contraceptives, theophylline, TCAs, warfarin. May reduce effects of guanfacine. Reduced metabolism and or increased toxicity with chloramphenicol, felbamate, MAOIs, valproic acid. May enhance the nephrotoxic effects of methoxyflurane. Potentially Fatal: Additive sedation and/or respiratory depression with ethanol, sedatives, antidepressants, opioid analgesics, benzodiazepines and other CNS depressants. May decrease levels/effects of antiarrhythmic drugs e.g. disopyramide, propafenone, quinidine.

Adverse Effects

Side effects of Phenobarbitone Sodium inj : 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 Potentially Fatal: Stevens-Johnson syndrome.

Mechanism of Action

Phenobarbitone is a short-acting barbiturate. It depresses the sensory cortex, reduces motor activity, changes cerebellar function, and produces drowsiness, sedation and hypnosis. Its anticonvulsant property is exhibited at high doses.