Epilepsy Flashcards
What are the three main types of generalised epilepsy?
Tonic-clonic (grand-mal)
Absence (petit-mal)
Myoclonic
What are the symptoms of Tonic-clonic seizures?
Loss of consciousness w/ full fit
Often w/o warning
What are the symptoms of Absence seizures?
Patient goes blank/staring for 10secs
Often in children
What are the symptoms of Myoclonic seizures?
Abrupt, shock-like jerks
Affects whole body/limbs
What is the main aim of Epilepsy treatment?
To control seizures with the lowest possible dose and the fewest side effects
What other pathologies can cause/present as seizures?
Cerebral tumours Cerebrovascular accident Alcohol withdrawal Hyper/hypoglycaemia Syphilis Drugs
What is the drug therapy for most generalised seizures?
1st line - Valproate/Carbamazepine/Lamotrigine
2nd line - Levitiracetam
MONOTHERAPY
What is the drug therapy for absence seizures?
1st line - Ethosuximide
2nd line - Valproate/Lamotrigine
MONOTHERAPY
How does Valproate work?
Potentiates GABA
Causes Na channel blockade
What are the side effects of Valproate?
Sedation Weight gain Tremor Birth defects Liver damage Thrombocytopenia
How does Carbamazepine work?
Use-dependent blockade of Na-channels
What are the side effects of Carbamazepine?
Rashes Dizziness Double vision Inducer of metabolism/many interactions Birth defects
How does Phenytoin work?
Voltage-dependent blockade of Na-channels
What are the side effects of Phenytoin?
Increased gum growth
Nystagmus
Birth defects
What sort of kinetics does Phenytoin have?
Zero-order
Disproportionate increases in plasma conc on increasing dose - MONITOR
How does Lamotrigine work?
Use-dependent blockade of Na-channels
Reduces glutamate release
What is the main side effect of Lamotrigine?
Bone marrow toxicity
-rash/flu like illness
Aplastic anaemia
What haematological effects can occur during treatment with anti-epileptic drugs?
Leucopenia -fever/sore throat/rash/mouth ulcers
Aplastic anaemia - Lamotrigine
Thrombocytopenia - Valproate
MONITOR FBC
What hepatological effects can occur during treatment with anti-epileptic drugs?
Hepatic function altered - Carbamazepine/Valproate
MONITOR LFT/INR
What skin effects can occur during treatment with anti-epileptic drugs?
Rashes
Stevens-Johnson/TEN - Carbamazepine, Lamotrigine, Phenytoin, Valproate
How should pregnant patients be advised regarding treatment?
Withdraw from drugs prior to conception if possible
Treatment is preferable to hypoxic seizures
Reduced control during pregnancy
Take folic acid to prevent NTD
Give Vit K1 in T3
What interactions are common with anti-epileptic drugs?
Phenytoin, Carbamazepine, Phenobarbitone are inducers
Failure of oral contraceptives
What drug is considered 1st line for treatment during pregnancy?
Lamotrigine - limited teratogenesis
What is Status Epilepticus?
Continuous seizures for 30 mins OR
2 fits w/o recovery between them
What is the treatment for Status Epilepticus?
Lorazepam i.v. OR Diazepam i.v./rectal OR Clonazepam OR Phenytoin i.v. OR General anaesthesia (propofol)
What are the main issues surrounding anti-epileptic treatment?
Driving (permitted if seizure free for 1 year)
Withdrawal (consider if seizure free for 2-4 years)
Pregnancy
Side effects
