Term
| Anticonvulsants/Antiepileptics: Hydantoins (Phenytoin [Dilantin]) |
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Definition
Prototype: Phenytoin [Dilantin]
Action: suppresses sodium influx -> stabilizes nerve cell membranes + reduces repetitive neuronal firing to limit seizures
- prevent seizures, but do not eliminate the cause or provide a cure; classified as CNS depressants
Contraindications:
- Pregnancy (leads to teratogenicity)
- Caution:
- low + slow ppl- hypothyroidism, hypotension, hypoglycemia
- CV problems- heart failure, dysrhythmias, cardiovascular disease
- mental/nerve problems- psychosis, suicidal ideation, depression, myasthenia gravis
- liver dysfunction- ETOH abuse, renal/hepatic impairment
- older adults, Asian ethnicity, pregnancy/breastfeeding
- diabetes mellitus, hypernatremia,
- Vitamin K deficiency, osteoporosis
Side effects:
- Teratogenicity- cleft lip/palate, microcephaly, missing fingers/toes (hypoplastic phalanges)
- EXCESS hair growth
- gingival hyperplasia/overgrowth
- cardiac dysrhythmias- bradycardia, heart block
- Depression, suicidal ideation
- Blood dyscrasias/low blood count
- Steven Johnson syndrome/rash
- ↓ insulin sensitivity + hyperglycemia if LT
Considerations:
- Dosage determined by age and BMR- newborns, elderly, and liver disease need a lower dosage (↓metabolism)
- Adjusted according to serum level- narrow therapeutic range (10–20 mcg/mL; toxic- above 20)
- Monitor renal/hepatic fx labs, serum level of drug, watch for side effects
Pt teaching:
- Female pts on oral contraceptives- use additional contraception methods
- Advise pts not to drive or operate heavy machinery while initiating drug therapy
- Stress importance of plaque removal if pt experiences gums overgrowth
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Term
| Anticonvulsant: Barbiturates (Phenobarbitol) |
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Definition
Action: reduces seizures by enhancing the activity of GABA (an inhibitory neurotransmitter)- used to prevent seizures
- narrow therapeutic range- 20-40 mcg/ml
Side/adverse effects:
- less teratogenic- better for pregnancy, still Kaiser
- Risk for sedation and and tolerance
- tolerance- may need to up dose periodically,
- should be tapered/discontinued gradually to avoid reoccurrence of seizures
Considerations:
- pt may develop tolerance- may need to up dose periodically
- discontinuation- should be tapered/discontinued gradually to avoid reoccurrence of seizures
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Term
| Anticonvulsants: Benzodiazepines (Diazepam [Valium], lorazepam) |
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Definition
Class: anxiolytics or minor tranquilizers
Action: enhances action of GABA - for short term tx of status epilepticus, anxiety/insomnia, preop sedation
Others: clonazepam (Klonopin) for reg prevention
Contraindications:
Side/adverse effects:
risk for tolerance- must be tapered off when discontinued
Considerations:
- drug has a short term effect so pt must be put on another anti-seizure med, (e.g. phenytoin, phenobarbitol) immed after for maintenance- if still having seizures, can repeat in 2-4 hrs
- CNS depressants have a risk for tolerance and must be tapered off when discontinued
Pt teaching:
avoid grapefruit, Sayville oranges, tangelos |
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Term
| Iminostillbanes: Carbamazepine |
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Definition
Action: suppresses Na influx to decrease neuroexcitability - prevents seizures
Contraindications:
Side effects:
- Agranulocytosis
- Steven Johnson syndrome
- Teratogenic- cleft lip/ palate + cardiac defects in fetus
- Vit K deficiency
- Grapefruit raises blood levels
Considerations:
- Preg women need daily folate supplements bc cause folate loss
Pt teaching:
NO GRAPEFRUIT |
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