Pharm E3, II Anticonvulsants

  1. Chronic seizure disorders are classified as...
    • Generalized
    • Focal
  2. Extracranial, Underlying causes for seizures (10):
    • Hypocalcemia
    • Hypoglycemia
    • Hypoxia
    • Hypo/Hypernatremia
    • Hyper-triglyceremia
    • Hepatic Encephalopathy
    • Uremic Encephalopathy
    • Polycythemia
    • Thiamin Def
    • Toxins
  3. Symptomatic, Intracranial, Underlying causes for seizures (9):
    • Head Trauma
    • Meningoencephalitis
    • Hydrocephalus (other congenital)
    • Cerebral Neoplasia
    • Lysosomal Storage Disorder
    • Acquired Cryptogenic Epilepsy
  4. Which type of seizure is most common in dogs?
    Generalized tonic-clonic (Grand-Mal)
  5. Status Epilepticus-
    When P fails to recover btw repeated tonic-clonic seizures, lasting for >30 mins
  6. Primary goals to inhibit seizures (3):
    • Increase seizure threshold
    • Reduce the spread of seizure discharge to surrounding neurons
    • Reduce Discharge of Focus (less common)
  7. Drug therapy efficacy... Complete Control: Partial Control: Little/No Control:
    • Complete: 50%
    • Partial: 25%
    • Little/None: 25%
  8. Drugs commonly used for status epilepticus:
    • Diazapam
    • Phenobarb
  9. Drugs traditionally used for long term control of seizures:
    • Phenobarb
    • KBr
    • (Primidone-hepatotoxic, Valpronic and Phenytion are limited in vet med)
  10. New drugs for long term control of seizures (5):
    • Felbamate
    • Gabapentine (neurontin)
    • Levetiracetan (Keppra)
    • Zonisamide (Zonegran)
    • Pregabalin (Lyrica)
  11. Which Anticonvulsant is metabolized in the liver?
    Phenobarb
  12. Which Anticonvulsant has active metabolites?
    Diazapam
  13. What are the active metabolites of Diazapam?
    • Nordiazepam
    • Oxazapam
  14. 1/2 Life of... (Dogs/Cats)
    Phenobarb:
    Bromide:
    Diazapam:
    • Phenobarb: 2-3d/1-3d
    • Bromide: 15-45d/10-11d
    • Diazapam: 3hrs/15-20hrs
    • (Dogs/Cats)
  15. Which Anticonvulsant is reabsorbed and excreted unchanged in the kidney?
    Bromide
  16. Side Fx of Diazapam (4):
    • Desation
    • Ataxia
    • Polyphagia
    • ACUTE HEPATIC NECROSIS
  17. Side Fx of Bromide(5):
    • Vomiting
    • Sedation
    • Polyphagia
    • PU/PD
    • Pelvic Limb Ataxia/Weakness
    • (Rare: Hyperactivity, pancreatitis, cutaneous lesions, Inflammatory Lung Dz)
  18. Tx Strategy for dogs
    • 1. Phenobarb
    • 2. Pehnobarb + KBr
    • 3. KBr alone
  19. Side Fx of Penobarb(7):
    • Sedation
    • Polyphagia
    • PU/PD
    • Pelvic Limb Ataxia/Weakness
    • Hepatotoxic (+ALT & ALKP)
    • Alter Bone Metab (Hematologic Fx)
    • Increased metab of various subs (+T4/FT4, Abx)
  20. Tx strategy for cats
    • 1. Phenobarb
    • 2. Benzodiazapine
    • 3. 3rd level drugs (primidone is toxic, and KBr=bronchial irritation)
  21. By which mechanisms does phenobarb supress seizures?
    • Increase threshold
    • Decrease Spread
  22. How does phenobarb work?
    • GABA mediated inhibition
    • Inhibits glutamate activity
    • Reduces Ca fluxes across mem
  23. How does Diazapam work?
    GABA Mediated Inhibition
  24. Drawbacks of Primidone:
    • Toxic to cats
    • Hepatotoxic
  25. What drung enhances the action of GABA?
    Benzodiazapine
  26. If Status Epilepticus doesn't respond to 2-3 doses of Diazapam, then admin...
    Phenobarb IV
  27. Drawbacks of using Propofol to Tx Seizures (2):
    • Hypotension
    • Respiratory Depression
    • (Expensive)
  28. In case of strychnine, ____ induces Status Epilepticus
    Pentobarbital
  29. How long until Steady State obtained with administration of....
    Phenobarb:
    Br:
    • Phenobarb: 10-16 days
    • Bromide: 3-4 Months
  30. T1/2 of...
    Phenobarb:
    Br:
    Diazapam:
    • Phenobarb: 47-74/25-76 hrs
    • Br: 15-45/10-11DAYS
    • Diazapam: 3.2/15-20 hrs
    • (Dogs/Cats)
  31. Which Anticonvulsants are contraindicated w/ Liver Dz?
    • Bromide
    • Diazapam
  32. Which Anticonvulsants are contraindicated w/ Lung Dz?
    Bromide
  33. Metabolism of Phenobarb
    Liver
  34. Metabolism of Bromide
    Unchanged in kidneys (reabsorbed= long 1/2 life)
  35. Metabolism of Diazapam
    • 1st Passage
    • Active Metabolites (Nordiazapam & Oxazapam)
  36. Diazapam's Active Metabolites
    • Nordiazapam
    • Oxazapam
  37. Which anticonvulsants have an additive effect?
    Bromide and Phenobarb
  38. Other/New Anticonvulsants (5):
    • Febamate
    • Gabapentine
    • Levitiracetam
    • Zonisamide
    • Pregabalin
  39. Alt to Benzodiazapam for cats
    Clonazepam
  40. Ways to protect brain function (5):
    • Barbituates
    • O2 therapy
    • Mannitol
    • Lasix
    • Elevate head 30o
  41. Ways to support systemic function (5):
    • Fluids
    • O2
    • Maint. Temp
    • Maint HR & BP
    • Ventilation (rarely)
  42. Most commonly used anticonvulsant
    Phenobarb
  43. Congener of Phenobarb:
    Primidone
  44. Primidone is converted to...
    • PEMA & Phenobarb
    • (PEMA HAS DELAYED TOXIC Fx!)
  45. Most potent elevator of threshold
    Benzodiazapam
  46. By which mechanisms do effective anti-convulsives suppress seizures?
    • Increase Threshol
    • Inhibit Spread
  47. Which drugs is ineffective in dogs when given PO?
    Diazapam
  48. Which drug requires a loading dose?
    KBr/NaBr
  49. During sever convulsions (i.e. strychnine toxicosis) when diazapam is ineffective, what other drugs should be administered?
    • Pentobarb
    • Propofol
Author
HLW
ID
75269
Card Set
Pharm E3, II Anticonvulsants
Description
Pharm E3 II, Anticonvulsants
Updated