NOT RECOMMENDED FOR USE WITHOUT SPECIALIST PALLIATIVE CARE SUPERVISION
Indication for use
- Terminal restlessness / delirium not responding to a combination of Midazolam and an anti-psychotic medication
Anticonvulsant in terminal phase
Formulation
Phenobarbital sodium for injection in 90% propylene (200mg/ml)
Prescribing for terminal sedation
- Give 100-200mg SC stat
- Followed by continuous subcutaneous infusion 600 mg / 24 hrs
- Dilute with WFI
- If previous heavy sedation has been required – start with 800 mg / 24 hrs
- Prescribe 200mg prn SC
- Increase the dose by increments of up to 400 mg / 24 hrs (up to a maximum dose of 1200 mg / 24 hrs
- May be useful to consider 12 hrly pump initially to assess response
Prescribing as an anticonvulsant
- If stat dose is indicated give 100mg SC / IM
- Then 200-400mg / 24 hrs CSCI
- Abrupt cessation of Phenobarbitone should be avoided because rebound seizures may be precipitated
- Phenobarbitone can alternatively be given as IV infusion:100mg Phenobarbitone in 100mls 0.9% saline over 30 minutes for rapid control followed by CSCI
Phenobarbitone is only miscible with Diamorphine and Hyoscine for use in CSCI
Do not mix with other drugs in syringe driver
Phenobarbitone must be diluted with water for use in CSCI
N.B. Phenobarbitone does not control hallucinations and may need to be given in combination with Haloperidol
References
Twycross R, Wilcock A, Thorp S. Palliative Care Formulary. PCF2.Radcliffe Medical Press 77-82
Heafield M. Managing Status Epilepticus. BMJ 2000;320:953-4