Epilepsy: Symptoms and Causes - NEET PG Medicine

Epilepsy is a common neurological condition that affects millions of people around the world, and therefore it is considered an important topic for medical PG exams. Studying epilepsy in the context of the NEET PG exam is rooted in its high prevalence, clinical relevance, diagnostic challenges, and therapeutic options.

In this blog, we have touched upon some important details about this high-yield medicine topic. Read on.

Overview

Epilepsy and seizures are not the same thing. Seizure means abnormal electrical activity due to some metabolic cause. Epilepsy is 2 or more than 2 unprovoked seizures. Convulsion is motor manifestation of seizure.

• International league against epilepsy (ILAE) 2017 classified epilepsy as focal seizures (earlier named as partial seizures). There are of the following types - 
  • Focal seizures with intact awareness
  • Focal seizures with impaired awareness.
  • Motor or Non-motor
    • Non motor means hallucinations e.g.: gustatory hallucinations, smell of burning kerosene or burning rubber, complex hallucinations in temporal lobe epilepsy.
    • Motor focal seizures include: Lip smacking, picking movements, automatism.
  • Generalized onset
    • Tonic-clonic
    • Myoclonic
    • Absence
• Generalized tonic clonic seizures- tonic means tone will increase and a person will give out a loud cry (ictal cry), after that patient falls. In clonus, there is intermittent relaxation also. So initially there is stiffness and after that there will be jerking movement and in between jerking movements muscles will relax. Most GTCS episodes terminate by themselves within one minute. Do not restrain the patient during GTCS as it may cause soft tissue injuries in this patient.
• Myoclonus: involuntary sudden jerky movement of limbs.
• Absence seizures: characterized by vacant staring spells.
• 5-10 % of the normal population will have at least one seizure with highest incidence in childhood/late adulthood. Overall incidence of epilepsy: 0.3-0.5%

Seizures	Syncope/vasovagal
Prodromal features	AURA is seen. Aura is visual blurring seen in migraine or focal seizures. (aura is not seen in GTCS)	Triggered by sight of blood, or on pain
Loss of consciousness	Minutes to hours	Few seconds to minutes.
Tonic clonic movements	Occurs for 30-60 seconds	Occurs for less than 15 seconds.
Facial appearance	Perioral cyanosis	Circum-oral paleness
Tongue bite	Sometimes	Rarely
Disorientation	++	+
Urinary incontinence	++	+
Headache	Sometimes	Rarely
Aching muscles	++

Important information Serum PROLACTIN level rises after an episode of convulsion.

Also Read: Myocardial Infarction - Neet PG Medicine

Drugs Used in Epilepsy

Generalized onset tonic Clonic	Focal	Typical absence	Atypical absence, Myoclonic, Atonic
First-Line
Lamotrigine Valproic acid	Lamotrigine Carbamazepine Oxcarbazepine Eslicarbazepine Phenytoin Levetiracetam	Valproic acid Ethosuximide Lamotrigine	Valproic acid Lamotrigine Topiramate

• In GTCS lamotrigine and valproate are given. Lamotrigine: side effects are Steven Johnson syndrome (SJS). Hence, lamotrigine is started at the lowest possible dose. Upon development of skin rash lamotrigine is stopped immediately. Valproate is highly teratogenic (7-20%). It causes neural tube defects. Hence it is not used in pregnancy. In pregnancy with GTCS lamotrigine or levetiracetam are used. 
• Carbamazepine: causes leukopenia, aplastic anemia, hepatotoxicity as a side effect. So, in a patient of liver damage carbamazepine is not given instead oxcarbazepine is given. Eslicarbazepine is given once/day. Phenytoin: phenytoin has nonlinear pharmacokinetics. So, toxicity can develop very fast, hence it is less preferred. Levetiracetam: It is used in elderly individuals due to lack of drug-to-drug interactions 
• In absence seizures the first line drug is Valproate, but if the age of child is less than 5 years ethosuximide is used.

When to Stop Epilepsy Medication?

Epilepsy medication can be stopped in the following scenarios - 

1. Complete medical control for 1-5 years.

2. Single seizure type 

3. Normal CNS examination including intelligence

4. No family history 

5. Normal EEG

• Reasonable to attempt withdrawal after 2 years if all of above are satisfied. Sudden stoppage of Anti-epilepsy medications can lead to rebound epilepsy (frequency, severity and duration of epilepsy can increase).

Important information Lennox-gastaut syndrome: Multiple seizure types in an individual

Also Read: EPILEPSY AND Electroencephalography (EEG) : NEET PG Medicine

Pregnancy and Epilepsy

• Valproate and topiramate are not used. All anti-epileptic drugs are teratogenic. But the most teratogenic drug is valproate (7-20% adverse fetal outcome).  Phenytoin, carbamazepine, oxcarbazepine causes decrease in vitamin K dependent clotting factors. This can increase the risk of hemorrhagic disease of the newborn. Safest antiepileptic drugs in pregnancy are levetiracetam and lamotrigine. If the patient comes in the 2nd or 3^rd trimester, continue the same anti-epileptic drug.
• Drug in breast milk /Drug in serum 
  • For valproate it is 5%
  • Levetiracetam: 300%
• Continue anti-epileptic drug in breastfeeding also, but watch for drowsiness and lethargy of baby, if excessive decrease the dose.

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