2. DEFINITION
Epilepsy
Epilepsy is a chronic disorder of brain
function characterized by recurrent
seizures often accompanied by episodes
of unconsciousness or amnesia.
Seizure
Seizure is a transient alteration in
behaviour because of disordered firing
of group of neurons.
17. Phenytoin
Blocks Na + Channels in Post
Synaptic NeuronInhibits the action
Potential of Neurons
18. ADVERSE EFFECTS
Nausea, vomitting, epigastric
pain Hypersensitivity
Megaloblastic anemia Teratogenicity
–when taken to the pregnant lady
,it produce fehydantoin syndrome
(Cleft Palate, Cleft lip &
Microcephaly)
Hyperglycemia
19. USES
1.Generalized tonic clonic seizures
and partial seizures
2.Status epileptics –phenytoin is used
by slow IV Injection.
3.trigeminal neuralgia – as an
alternative to carbamazepine.
4.cardiac arrhythmias- phenytoin is
useful in digitalis induced arrhythmias.
20. Drug interaction
Phenytoin is an enzyme inducer.
phenobarbitone competitively inhibit s
phenytoin metabolism.
Carbamazepine and pheytoin enhances
each others metabolism.
Valproate displace protein bound and
may result in phenytoin toxicity.
Antacid absorption of phenytoin.
21. Fosphenytoin
It is a prodrug of phenytoin that has
certain advantages over phenytoin for
Parenterally use:
It is quickly converted to phenytoin in
the body.
More potent.
Less cardiotoxic.
Safer on the intestine.
22. PHENOBARBITONE
It has specific antiepileptic activity.
Primidone which is rarely used .
Phenobarbitone is effective in tonic-
clonic seizures and ineffective in absence
of seizures.
23. MECHANISM OF ACTION
Acts on the Synapse
Enhance the action of Inhibitory
neurotransmitters (Eg. GABA)
Suppresses the excitatory neurotransmitters (Ach)
Opens Cl – ion Channels
Decreases the Seizures
26. CARBAMAZEPINE
Carbamazepine is a tricyclic
compound Anti seizure activity
It has good Anti seizure activity .its
mechanism of action and anti epileptic
action are similar to phenytoin.
Carbamazepine is also used in the
treatment of trigeminal neuralgia
28. VALPORIC ACID MoA
Enhances the level of GABA (se
Metabolism of GABA)
Blocks Na + Channels
Decreases low threshold Ca + current in
thalamus
Reduce Seizure
29. ADVERSE EFFECTS
Sedation, Rashes, Ataxia and Tremors
USES
Partial & Generalized Seizures
Useful particularly in Absence Seizures (Petit
Mal Seizures)
Generalized Tonic Clonic Attacks
30. BENZODIAZEPINE
Diazepam is the drug of choice in status
epilepticus.
Clonazepam is a potent anti epileptic drug
useful in absence and myoclonic seizures.
Nitrazepam is used for treatment of
myoclonic seizures.
31. NEWER ANTI
EPILEPTICS
Gabapentin – It is a highly lipid soluble
drug.
It crosses the BBB.
Effective in tonic clonic seizure
Exact MoA is unknown.