MHRA advice: Valproate (Belvo, Convulex, Depakote, Dyzantil, Epilim, Epilim Chrono or Chronosphere, Episenta, Epival, and Syonell): new safety and educational materials to support regulatory measures in men and women under 55 years of age (January 2024) (www.gov.uk).
National Patient Safety Alert: Valproate: organisations to prepare for new regulatory measures for oversight of prescribing to new patients and existing female patients (November 2023) (www.gov.uk).
MHRA advice: Antiepileptic drugs in pregnancy: updated advice following comprehensive safety review (January 2021) (www.gov.uk).   
MHRA advice: Antiepileptic drugs: updated advice on switching between different manufacturers’ products (November 2017) (www.gov.uk). 
MHRA advice: Antiepileptics: risk of suicidal thoughts and behaviour (December 2014) (www.gov.uk). 
SPS article: Using contraception with enzyme-inducing medicines (Feb 2023).
Also see BNF: Epilepsy.

  • Refer to guidance on Management of prolonged seizures.
  • Midazolam (or in occasional circumstances rectal diazepam) is used for clusters or prolonged generalised seizures.  
  • Note: Complex partial status epilepticus with loss of awareness is treated as for convulsive status epilepticus.
  • Intramuscular diazepam is not recommended for rescue medication.

MIDAZOLAM

Important: Therapy notes

  • Intranasal or buccal midazolam is used in accordance with Highland guidelines for staff administering and providing training in the use of buccal (or nasal) midazolam, and ‘Local protocol for midazolam use in Learning Disability In-patient services in New Craigs Hospital’.  Refer to specialist for advice. 
  • Note: Plasma midazolam concentrations are markedly increased by co-administration of CYP3A4 inhibitors eg antibacterials (erythromycin, clarithromycin) and antifungals (ketoconazole, itraconazole, and fluconazole).
    After a single dose of oromucosal midazolam in patients on these drugs, careful monitoring of the clinical effects and vital signs is recommended; for further information see Epistatus SPC.
  • Brand name prescribing is recommended to ensure carers receive the brand they have been trained to use.

Important: Formulation and dosage details

Formulation:

Oromucosal solution pre-filled oral syringe (Epistatus®) (CD schedule 3) 10mg/mL, 7.5mg/0.75mL, 5mg/0.5mL, 2.5mg/0.25mL (specialist initiation by epilepsy service only)

Dosage:

Intranasally or buccally

These are single use syringes that do not have incremental dosing. NOT to be used for part doses.To be prescribed as the brand 'Epistatus'.

Important: Formulation and dosage details

Formulation:

Oromucosal solution (Epistatus®) (CD schedule 3) 50mg/5mL unlicensed (specialist initiation)

Dosage:

Intranasally or buccally, 10mg. 

initiation by epilepsy service only

Important: Formulation and dosage details

Formulation:

Solution for injection (CD Schedule 3) 5mg/5mL, 50mg/50mL

Dosage:

Intranasally or buccally 10mg. 

DIAZEPAM

Important: Therapy notes

MHRA advice: Drugs and driving: concentration limits to be set for certain controlled drugs in a new legal offence (December 2014) (www.gov.uk).

Important: Formulation and dosage details

Formulation:

Rectal solution tubes 5mg/2.5mL, 10mg/2.5mL

Dosage:

Adult and child over 12 years:
By rectum: 10mg, repeated once after 10 to 15 minutes if necessary.

Important: Formulation and dosage details

Formulation:

Emulsion for injection 10mg/2mL

Dosage:

Adult and child over 12 years:
By intravenous injection:
 10mg at a rate of 0.5mL (2.5mg) per 30 seconds, repeated once after 10 minutes if necessary.

Notes:

Intravenous infusion of diazepam is potentially hazardous (especially if prolonged) calling for close and constant observation and best carried out in a hospital with intensive care facilities. Diazemuls® injection is licensed for intravenous administration only.

LORAZEPAM

Important: Therapy notes

MHRA advice: Drugs and driving: concentration limits to be set for certain controlled drugs in a new legal offence (December 2014) (www.gov.uk).

  • Lorazepam as a bolus is preferable to diazepam because of its long duration of antiepileptic action.

Important: Formulation and dosage details

Formulation:

Solution for injection 4mg/mL

Dosage:

By slow intravenous injection (into large vein) 4mg.

LEVETIRACETAM

Important: Therapy notes

Important: Formulation and dosage details

Formulation:

Concentrate for solution for infusion 500mg/5mL (s)

Dosage:

For use where other medicines are contra-indicated.

PARALDEHYDE

Important: Therapy notes

Available from special-order manufacturers; for information contact Medicines Information.

Important: Formulation and dosage details

Formulation:

Enema 50% in olive oil (s) unlicensed

Dosage:

Use in Paediatrics in accordance with BNF for Children

PHENYTOIN

Important: Therapy notes

NHS Improvement Patient Safety Alert: Risk of death and severe harm from error with injectable phenytoin (November 2016): Use of injectable phenytoin is error-prone throughout the prescribing, preparation, administration and monitoring processes; all relevant staff should be made aware of appropriate guidance on the safe use of injectable phenytoin to reduce the risk of error.

Important: Formulation and dosage details

Formulation:

Solution for injection 250mg/5mL

Dosage:

Refer to phenytoin dose calculations.

SODIUM VALPROATE

Important: Therapy notes

Note: risk of abnormal pregnancy outcomes, liver dysfunction and contraindication in patients with certain mitochondrial disorders.

Valproate medicines are contraindicated in women and girls of childbearing potential unless conditions of Pregnancy Prevention Programme are met (MHRA advice April 2018)

  • MHRA advice: Valproate: dispense full packs of valproate-containing medicines (October 2023) (www.gov.uk).
  • MHRA advice: Valproate: reminder of current Pregnancy Prevention Programme requirements; information on new safety measures to be introduced in the coming months (December 2022) (www.gov.uk).
  • MHRA advice: Antiepileptic drugs in pregnancy: updated advice following comprehensive safety review (January 2021) (www.gov.uk).
  • MHRA advice: Valproate Pregnancy Prevention Programme: temporary advice for management during coronavirus (COVID-19) (May 2020) (www.gov.uk).
  • MHRA advice: Valproate (Epilim▼, Depakote▼) pregnancy prevention programme: updated educational materials (February 2020) (www.gov.uk).
  • MHRA advice: Antiepileptic drugs: updated advice on switching between different manufacturers’ products (November 2018) (www.gov.uk).
  • Risk Minimisation Materials
  • MHRA Drug Safety Update articles
  • Plasma concentrations do not always correlate with efficacy, hence routine monitoring is usually unhelpful.

Important: Formulation and dosage details

Formulation:

Solution for injection 300mg/3mL (s)

Dosage:

For emergency use only. 

Editorial Information

Document Id: F079