MHRA/CHM Flashcards
Category 1
Patient must be maintained on a specific brand/generic drug manufacturer.
Category 1 - drugs
Phenytoin (Epanutin)
Phenobarbital
Carbamazepine (Tegretol)
Primidone
Category 2
Patient maintained on a specific brand based on clinical judgement e.g. seizure frequency, treatment history
Category 2 - drugs (common)
Valproate
Lamotrigine
Clobazam
Oxcarbazepine
Clonazepam
Topiramate
Category 2 - drugs (less common)
Perampanel
Retigabine
Rufinamide
Zonisamide
Eslicarbazepine
Category 3
Patient does NOT need to be maintained on a specific brand
Category 3 - drugs (common)
Levetiracetam
Gabapentin
Pregabalin
Lacosamide
Category 3 - drugs (less common)
Tiagabine
Ethosuximide
Vigabatrin
Suicidal thoughts/behaviour
- Risk with all anti-epileptic drugs
- Can occur within 1 week of starting treatment
- Advise patients to report any mood changes, distressing thoughts/feelings about suicide or self-harm
- Seek help
- Do not stop/switch medication without professional advice
Antiepileptic Hypersensitivity Syndrome (AHS)
Occurs within 8 weeks of exposure to medication
Discontinue immediately and seek specialist advice.
Occurs with all Category 1 drugs AND lamotrigine
* Rash
* Fever
* Lymphadenopathy
Withdrawal
- Avoid abrupt withdrawal - can precipitate severe rebound seizures
- Gradually reduce dose under specialist supervision
- Withdraw one antiepileptic drug at a time
- Benzodiazepines and Barbiturates require longer to reduce dose.
Driving
Can drive if:
* Seizure free for 1 year.
* Established seizure pattern with no influence on consciousness
* No history of unprovoked seizures.
* Seizure due to prescribed change or withdrawal
* History of no awake seizures for 1 year from first sleep seizure.
* Established pattern of sleep seizures for 3 years is previous awake seizure.
Pregnancy
Antiepileptic medicines have an increased risk of teratogenicity.
Particularly in the 1st trimester or if using more than 1 epilepsy medication
Teratogenicity - highest risk
Valproate/valproic acid
Minor and major congenital malformation + long-term developmental disorders.
Teratogenicity - increased risk
Carbamazepine
Phenytoin (anti-folate)
Phenobarbital
Primidone
Lamotrigine
Topiramate
Risk of cleft palate if used in 1st trimester
Pregnancy - general advice
- Refer to specialist if planning a pregnancy
- Notify the UK epilepsy and pregnancy register
- Folic acid 5 mg OD (pre-conception and during 1st trimester) - reduces the risk of neural tube defects.
- Vitamin K injection - minimises risk of neonatal haemorrhage
Pregnancy - monitor foetal growth
- Topiramate
- Levetiracetem
Pregnancy - monitor plasma drug conc.
Adjust dose based on plasma-drug concentration.
* Phenytoin
* Carbamazepine
* Lamotrigine
For other drugs, dose adjustments are made based on clinical judgement.
Breastfeeding
Avoid abrupt withdrawal of BF - risk of withdrawal symptoms especially with phenobarbital/primidone
Monitor infants for:
* Drowsiness
* Weight gain
* Feeding difficulty
* Adverse effects
* Developmental milestones
What drugs are present in high amounts in breastmilk?
ZELP
* Zosinamide
* Ethosuximide
* Lamotrigine
* Primidone
What drugs accumulate due to slower metabolism in infants?
- Phenobarbital
- Lamotrigine
What drugs inhibit the sucking reflex?
- Phenobarbital
- Primidone
What drugs cause drowsiness in babies?
- Benzodiazepines
- Phenobarbital
- Primidone