Epilepsy

1. EPILEPSY Abdul Waheed M.Pharm -Pharmacology Department of Pharmacology Amity University Noida

2. Epileptic seizure Abnormal synchronous discharge of the cortex leading to transient dysfunction of the brain A seizure can be evoked by any pathology affecting the brain, transient or permanent

3. Types of seizures Generalised seizures Tonic - clonic Tonic Clonic Atonic Absence Myoclonus Focal (partial) seizures Simplex partial Complex partial Partial onset with secondary generalisation

4. Generalised tonic-clonic seizure (grand mal) The most common seizure Acute symptomatic seizures are generalised tonic-clonic seizures Course: Cry, loss of consciousness, fall Tonic phase- generalised muscle contraction, apnoe a Clonic phase- rhythmic contraction of muscles, tongue bite, foaming, enuresis Terminal sleep and gradual regaining of consciousness (transient confusion)

5. Absence Cognitive dysfunction with a sudden onset and end, lasting 5-10 seconds Stare, expressionless face; arrest of ongoing activity; generally no motor phenomena EEG: generalised 3 Hz spike and wave activity Occurs in genetic (idiopathic) epilepsies, mostly in children

6. Myoclonic seizure Sudden, quick, arrhythmic muscle contraction, twitch of a limb; no loss of consciousness EEG: generalised polyspike and wave activity Occurs in genetic (idiopathic) epilepsies Not only an epileptic phenomenon- it can be the sign of diffuse encephalopathies

7. Simplex partial seizures No loss of consciousness Symptoms depend on area of brain involved: Motor Sensory Autonomic Psychosensory It can be the introductory phase of a complex partial or generalised tonic-clonic seizure (‘aura’)

8. Complex partial seizures Origin is most often in the temporal lobe A common seizure type in adulthood Can be introduced by a simplex partial psychosensory seizure: olfactory hallucination déj à vu, jamais vu feeling of alienation Loss of consciousness: stare, ‘going blank’ Automatisms: oral automatisms fiddling with the hands

9. TREATMENT OF EPILEPSY CLASSIFICATION 1.Barbiturate Phenobarbitone 2.Deoxybarbiturate Primidone 3.Hydantoin Phenytoin,Fosphenytoin 4.Iminostibene Carbamazepine , Oxacarbazepine 5.Succinimide Ethosuximide 6.Aliphatic carboxylic acid Valproic acid(sodium valproate ) 7.Benzodiazepines Clonazepam,Diazepam,Lorazepam,Clobazam

10. 8.Phenytrizine Lamotrigine 9.Cyclic GABA analogue Gabapentin 10.Newer drugs Vigabatrin , Topiramate , Tiagabin , Zonisamide , Levetiracetam

11. Mechanism of action of AEDs Inhibition of voltage gated Na, Ca channels Na: phenytoin, carbamazepine, oxcarbazepine, lamotrigine, topiramate, felbamate, zonisamide Ca: ethosuximid, valproate? lamotrigine, topiramate, zonisamide Potentiaton of GABA mediated inhibition phenobarbital, benzodiazepins, vigabatrin, tiagabine, topiramate, valproate, gabapentin, felbamate Decrease of glutamate mediated excitation felbamate, topiramate

12. Side effects of AEDs Allergy Central nervous system side effects (dose dependent) drowsiness, headache dizziness, dysequilibrium cognitive dysfunction (memory) Idiosynchratic reactions / chronic side effects bone marrow suppression hepatic failure rash weight gain, weight loss tremor polycystic ovary syndrome visual field defect

13. Thank you