Antiepileptic Drugs Chapter 14 Flashcards
carbamazepine** (Tegretol-XR, Tegretol)
CLASS/ INDICATIONS
ANTIEPILEPTIC DRUGS: Chapter 14
CLASS: Iminostilbenes
INDICATIONS: Partial, secondary generalized, generalized tonic-clonic seizures
carbamazepine** (Tegretol-XR, Tegretol)
DOSAGES/ THERAPEUTIC PLASMA LEVELS
PO: 12 400-1200 mg/day
THERAPEUTIC PLASMA LEVEL 4-12 mcg/mL
carbamazepine** (Tegretol-XR, Tegretol)
ADVERSE EFFECTS
ADVERSE EFFECTS:nausea, headache, dizziness, unusual eye movements, visual change, behavioral changes, rash, abdominal pain, abnormal gait
carbamazepine** (Tegretol-XR, Tegretol)
NURSING IMPLICATIONS/ CONTRAINDICATIONS
NI: associated with autoinduction of hepatic enzymes (within 2 months of initial treatment)
CT: may worsen byoclonic or absence seizures; bone marrow depression
carbamazepine** (Tegretol-XR, Tegretol)
DRUG INTERACTIONS
Altered CYP450 enzyme metabolism: increased carbamazepine levels and toxicity risk (azole antifungals, diltiazem, isoniazid, macrolides, protease inhibitor antiretrovirals, SSRIs, valproic acid, verapamil)
Altered CYP450 enzyme metabolism: reduced carbamazepine levels and efficacy (barbiturates, hydantoins, rifampin, succinimides, theophyline)
Altered CYP450 enzyme metabolism: increased hepatic metabolism of acetaminophen and toxicity risk, reduced efficacy (acetaminophen
Altered CYP450 enzyme metabolism: reduced efficacy; pt response must be monitored (antipsychotics, antidepressants, benzodiazepines, cyclosporine, oral contraceptives)
Altered CYP450 metabolism: Increased MAOI toxicity risk (MAOIs)
gabapentin** (Neurontin)
CLASS/ INDICATIONS
ANTIEPILEPTIC DRUGS: Chapter 14
CLASS: Miscellaneous
INDICATIONS: Partial, secondary generalized seizures, neuropathic pain, adjunct partial seizures/ prophylaxis of partial seizures
gabapentin** (Neurontin)
DOSAGES
Pediatric: PO: 10-15 mg/kg/day divided tid, then adjust
Adult PO: older than 18 yr, 900-1800 mg/day
gabapentin** (Neurontin)
ADVERSE EFFECTS
CNS and GI symptoms, dizziness, drowsiness, nausea, visual and speech changes, edema
gabapentin** (Neurontin)
NURSING IMPLICATIONS/ CONTRAINDICATIONS
CT: known drug allergy
gabapentin** (Neurontin)
DRUG INTERACTIONS
Additive CNS depression: Increased CNS depression (alcohol)
phenobarbital**
CLASS/ INDICATIONS
ANTIEPILEPTIC DRUGS: Chapter 14
CLASS: Barbiturate
INDICATIONS: Pediatric; Partial, secondary generalized, geralized tonic-clonic seizures, prophylaxis for febrile seizures, psychomotor seizures
INDICATIONS: Adult; partial, secondary generalized, generalized tonic-clonic seizures
phenobarbital**
DOSAGES/ THERAPEUTIC PLASMA LEVELS
ORAL, INJECTABLE
Pediatric: PO: 3-6 mg/kg/day
Adult: PO: 1-3 mg/kg/day
THERAPEUTIC PLASMA LEVELS: 10-40 mcg/mL
phenobarbital**
ADVERSE EFFECTS
Dizziness, drowsiness, lethargy, paradoxical restlessness
phenobarbital**
NURSING IMPLICATIONS/ CONTRAINDICATIONS
CT: sedation, known drug allergy, porphyria liver/ kidney impairment, respiratory illness, adverse effects include cardiovascular, CNS, GI , dermatologic reactions
phenytoin** (Dilantin)
CLASS/ INDICATIONS
ANTIEPILEPTIC DRUGS: Chapter 14
CLASS: Hydantoin
INDICATIONS: Pediatric; partial secondary generalized, generalized tonic-clonic seizures;
INDICATIONS: Adult; generalized tonic-clonic seizures
phenytoin** (Dilantin)
DOSAGES/ THERAPEUTIC PLASMA LEVELS
Pediatric: PO: 5-10 mg/kg/day
Adult: PO: 300-600 mg/day
THERAPEUTIC PLASMA LEVELS: 10-20 mcg/mL
phenytoin** (Dilantin)
NURSING IMPLICATIONS/ CONTRAINDICATIONS
NI: Highly protein bound, exaggerated effects in pts with low serum albumin (malnourished or renal failure)
CT: known drug allergy and heart conditions that involve bradycardia or blockage of electrocardiac function
phenytoin** (Dilantin)
ADVERSE EFFECTS
Nystagmus, ataxia, drowsiness, rash, gingival hyperplasia, thrombocytopenia, agranulocytosis, hepatitis
phenytoin** (Dilantin)
DRUG INTERACTIONS
Altered CYP450 enzyme metabolism: reduced hydantoin clearance and increased effects (amiodarone, benzodiazepines, azole antifungals, isoniazid, proton pump inhibitors, sulfonamide antibiotics, SSRIs,)
Altered CYP450 enzyme metabolism: increased hydantoin clearance and reduced effects (carbamazepine)
Displacement of warfarin from plasma protein binding sites: increased free warfarin levels and bleeding risk (warfarin)
valproic acid** (Depacon, IV Depakote, Depakene oral)
CLASS/ INDICATIONS
ANTIEPILEPTIC DRUGS: Chapter 14
CLASS: Miscellaneous
INDICATIONS: generalized tonic-clonic, absence, myoclonic seizures
valproic acid** (Depacon, IV Depakote, Depakene oral)
DOSAGES/ THERAPEUTIC PLASMA LEVELS
Adult and pediatric
PO: 15-60 mg/kg/day divided bid-tid
IV: 10-15 mg/kg/day as a 60-min infusion
THEAPEUTIC PLASMA LEVELS: 50-100 mcg/mL
valproic acid** (Depacon, IV Depakote, Depakene oral)
NURSING IMPLICATIONS/ CONTRAINDICATIONS
NI: Highly bound to plasma proteins: competes with other highly protein-bound medications
CT: known drug allergy, liver impairment, and urea cycle disorders
valproic acid** (Depacon, IV Depakote, Depakene oral)
ADVERSE EFFECTS
Dizziness, drowsiness, GI upset, weight gain, hepatoxicity, pancreatitis
valproic acid** (Depacon, IV Depakote, Depakene oral)
DRUG INTERACTIONS
Displacement of valproic acid from plasma protein binding sites: increased free valproic acid levels and toxicity risk (aspirin)
Altered CYP450 enzyme metabolism: reduced valproic acid efficacy, increased lamotrigine levels, increased or decreased carbamazepine levels (carbamazepine, oxcarbazepine, lamotrigine)
Altered hepatic metabolism: increased lorazepam toxicity risk (lorazepam)
Altered CYP450 enzyme metabolism: reduced valproic acid efficacy (rifampin)
Altered CYP450 enzyme metabolism: increased tricyclic antidepressant toxicity risk (tricyclic antidepressants)
