101 Flashcards
Front
Back
What are the main features of epilepsy?
Epilepsy is characterized by convulsive seizures, sensory disturbances, abnormal behaviour, and loss of consciousness.
What percentage of epilepsy cases are idiopathic, and what is the cause?
70% of cases are idiopathic; cause unknown, may involve inherited CNS abnormalities.
What are secondary causes of epilepsy?
Secondary causes: Reversible (trauma, head injury, hypoglycemia, meningitis) and irreversible (cerebrovascular disorders).
Define simple partial seizures.
Motor seizures begin in a restricted region, progressing gradually, with consciousness preserved.
Define complex partial seizures.
Associated with automatisms and impairment of consciousness.
What are simple partial seizures with secondarily generalized tonic-clonic seizures?
Partial epilepsy followed by tonic-clonic (grand mal) seizures.
Define generalized seizures (grand mal epilepsy).
Sudden loss of consciousness, muscular contractions, rigidity, teeth clenching, tongue biting, incontinence, postictal headache, and confusion.
What are the features of absence seizures (petit mal epilepsy)?
Abrupt onset, staring, cessation of activity, lasting <30 seconds without loss of postural control.
What are myoclonic seizures?
Brief, shock-like contractions lasting seconds, localized or generalized.
What are febrile seizures?
Seizures triggered by high fever, common between ages 6 months to 6 years.
What is status epilepticus?
Life-threatening continuous seizures (>15-30 mins) without full recovery of consciousness.
What are barbiturates and related substances used in epilepsy?
Phenobarbital and primidone are used to treat epilepsy.
List the pharmacokinetics of primidone.
Primidone is metabolized to phenobarbital; anticonvulsant doses do not cause excessive sedation.
What is the mechanism of action of phenytoin?
Blocks sodium channels, inhibits calcium influx, antagonizes glutamate, and modulates neurotransmitters.
What are the pharmacokinetics of phenytoin?
Slow oral absorption, high brain concentration, protein-bound, and hepatic metabolism.
List the indications of phenytoin.
Tonic-clonic seizures, partial epilepsy, status epilepticus (IV), ventricular arrhythmias.
What are the CNS side effects of phenytoin?
Nystagmus, ataxia, blurred vision, drowsiness, tremor, headache, hallucination, confusion.
What are the GIT and systemic side effects of phenytoin?
Nausea, vomiting, gingival hyperplasia, hirsutism, coarsened facial features, teratogenic effects.
What are tricyclic compounds used in epilepsy?
Carbamazepine and oxcarbazepine.
What is the mechanism of action of carbamazepine?
Blocks sodium channels, inhibits norepinephrine reuptake, potentiates GABA.
What are the indications of carbamazepine?
Partial seizures, tonic-clonic seizures, trigeminal neuralgia, manic-depressive patients.
What are the adverse effects of carbamazepine?
Drowsiness, ataxia, liver/kidney issues, aplastic anemia, hyponatremia, Stevens-Johnson syndrome.
What benzodiazepines are used as antiseizure drugs?
Diazepam, nitrazepam, clonazepam, lorazepam.
What are the mechanisms of action of valproic acid?
Blocks sodium channels, increases GABA, blocks NMDA receptors, activates potassium channels.
What are the indications of valproic acid?
Absence seizures, juvenile myoclonic epilepsy, tonic-clonic seizures, partial epilepsy, migraine prophylaxis, bipolar disorder.
List the adverse effects of valproic acid.
Nausea, vomiting, alopecia, tremors, sedation, thrombocytopenia, teratogenic effects.
What is the mechanism of action of ethosuximide?
Inhibits T-type calcium channels in thalamic neurons.
What are the side effects of ethosuximide?
Nausea, vomiting, agitation, behavioral changes, gastric upset.
What is the mechanism of action of vigabatrin?
Irreversibly inhibits GABA-aminotransferase.
What are the indications of vigabatrin?
Partial epilepsy, West syndrome.
What is the mechanism of action of tiagabine?
Inhibits GABA transporter GAT-1, increasing GABA levels in the brain.
What are the indications of tiagabine?
Partial epilepsy, tonic-clonic seizures.
What are gabapentin & pregabalin used for?
Partial epilepsy, grand mal epilepsy, and neuropathic pain (e.g., postherpetic neuralgia).
What is the mechanism of action of lamotrigine?
Blocks sodium channels, acts on calcium channels.
What are the adverse effects of lamotrigine?
Nausea, headache, drowsiness, rash, dermatitis.
What is the mechanism of action of topiramate?
Blocks sodium channels, enhances GABA activity.
List the indications of topiramate.
Partial epilepsy, tonic-clonic seizures.
What are the adverse effects of felbamate?
Severe hepatitis, aplastic anemia.
What is levetiracetam used for?
Adjunct therapy for partial, myoclonic, and generalized tonic-clonic seizures.
What are the advantages of newer antiseizure drugs?
Lower side effects, minimal serum monitoring, fewer drug interactions.
What is the mechanism of action of zonisamide?
Blocks sodium and calcium channels.
What is the main antiseizure action of acetazolamide?
Inhibits carbonic anhydrase, causing metabolic acidosis.
What is the significance of monitoring therapeutic drug levels in epilepsy treatment?
Ensures effective drug levels, guides EEG and liver function monitoring.
What pediatric considerations should be taken with anticonvulsants?
Young patients face higher risks like gingival hyperplasia, hepatotoxicity, and impaired school performance.
Front
Back
What are the reversible secondary causes of epilepsy?
Trauma, head injury, hypoglycemia, meningeal infections.
What are the irreversible secondary causes of epilepsy?
Cerebrovascular disorders.
What characterizes Jacksonian seizures?
Motor seizures starting in a specific region like fingers, progressing without loss of consciousness.
What are automatisms in complex partial seizures?
Purposeless movements like lip smacking, chewing, hand wringing, or aimless walking.
What are postictal phenomena of generalized seizures?
Headache, confusion, fatigue following generalized seizures.
What are the clinical signs of tonic-clonic seizures?
Loss of consciousness, postural control, rigidity, teeth clenching, and incontinence.
What are the features of febrile seizures?
Seizures triggered by high fever, typical between 6 months and 6 years.
Define the mechanism of action of primidone.
Primidone is metabolized to phenobarbital, providing anticonvulsant effects without sedation.
What is the primary action of hydantoins in epilepsy treatment?
Blocks voltage-gated sodium channels, modulates neurotransmitter activity.
How does phenytoin affect insulin secretion?
Phenytoin inhibits insulin secretion, causing hyperglycemia and glycosuria.
What are the teratogenic effects of phenytoin?
Cleft lip, cleft palate, congenital heart defects, growth retardation.
What differentiates oxcarbazepine from carbamazepine?
Oxcarbazepine has a longer action and less enzyme induction compared to carbamazepine.
What is the role of benzodiazepines in infantile spasms?
Benzodiazepines like clonazepam are effective in suppressing infantile spasms.
How does valproic acid act on NMDA receptors?
Valproic acid blocks NMDA receptor-mediated excitation, reducing neuronal excitability.
What are the teratogenic effects of valproic acid?
Spina bifida, cardiovascular anomalies, orofacial and digital anomalies.
Why is ethosuximide the first choice for absence seizures?
Ethosuximide inhibits T-type calcium channels, specifically effective in absence seizures.
What is the primary action of vigabatrin on GABA?
Irreversibly inhibits GABA degradation, increasing its availability in the brain.
What is the significance of GAT-1 inhibition by tiagabine?
Inhibits GABA uptake, increasing GABA concentrations in forebrain and hypothalamus.
What are common side effects of gabapentin and pregabalin?
Drowsiness, dizziness, headache, fatigue, usually resolving within two weeks.
What distinguishes lamotrigine as an antiepileptic?
Blocks sodium channels, reduces neuronal firing in partial and generalized seizures.
What are the cognitive side effects of topiramate?
Decreased cognitive function, paresthesia, nervousness, confusion.
Why is felbamate considered third-line treatment?
Severe toxicity risks like aplastic anemia and hepatitis limit its use.
What are the unique advantages of levetiracetam?
Minimal side effects, no need for serum monitoring, once-daily dosing.
How does zonisamide act on calcium channels?
Blocks voltage-dependent calcium channels, reducing neuronal hyperexcitability.
What role does acetazolamide play in women with seizure exacerbations during menses?
Used as an alternative treatment for epilepsy, especially during menstruation.
What are common pediatric considerations for hydantoins?
Young patients experience gingival hyperplasia, hirsutism, and impaired school performance.