Carbamazepine

Aka: Carbamazepine, Tegretol

1. Indication
   1. Simple Partial Seizures
   2. Complex Partial Seizures
   3. Generalized Tonic Clonic Seizures
   4. Trigeminal Neuralgia
   5. Bipolar Disorder
      1. Frequently reserved for use as a second agent
   6. Resistant Schizophrenia
   7. Restless Leg Syndrome
   8. Psychosis in Dementia
   9. Post-Traumatic Stress Disorder
2. Contraindications
   1. MAO inhibitor use within last 14 days
   2. Bone Marrow depression
   3. Pregnancy
3. Precautions
   1. Do not use in Asian patients unless they are negative for HLA-B1502
      1. Risk of Steven's Johnson: 5% if HLA-B1502 positive
      2. FDA has issued a black box warning
      3. Man (2007) Epilepsia 48(5):1015-8
4. Adverse Effects: Dose related
   1. Gradual tolerance to side effects
   2. Lethargy
   3. Nausea and Vomiting
   4. Tremor
   5. Ataxia
   6. Diplopia
5. Adverse Effects: Other
   1. Morbilliform rash
   2. Leukopenia
   3. Agranulocytosis
   4. Aplastic Anemia
   5. Cardiac conduction abnormality (increases A-V delay)
   6. Hyponatremia (SIADH risk in elderly)
   7. Liver failure
   8. Osteoporosis
   9. Serum Sickness
   10. Stevens-Johnson Syndrome
6. Drug Interactions (Numerous)
   1. Substrate of Cytochrome P450 2C8/9
   2. Substrate of Cytochrome P450 3A4
   3. Induces Cytochrome P450 1A2
   4. Induces Cytochrome P450 2B6
   5. Induces Cytochrome P450 2C8/9
   6. Induces Cytochrome P450 2C19
   7. Induces Cytochrome P450 3A4
7. Dose: General
   1. Titrate dose to serum concentration and effect
   2. Target serum concentration: 4-12 mcg/ml
      1. Observe closely for concentration 8 mcg/ml or higher
   3. Toxic serum concentration: >15 mcg/ml
8. Dose: Adults
   1. Seizure Disorder
      1. Initial: 200 mg PO bid
      2. Increase by 200 mg/day increments weekly
      3. Target: 800-1200 mg/day divided tid - qid
   2. Trigeminal Neuralgia
      1. Initial: 100 mg PO bid
      2. Increase by 100 mg/day increments weekly
      3. Target: 400-800 mg/day divided bid
9. Dose: Elderly
   1. Initial: 100 mg PO bid
   2. Increase by 100 mg/day increments weekly
   3. Target: 400-1000 mg/day divided tid - qid
10. Monitoring: Periodic labs
    1. Complete Blood Count with Platelet Count
    2. Serum Iron
    3. Liver Function Test
    4. Urinalysis
    5. Serum Sodium
    6. Blood Urea Nitrogen
    7. Thyroid Stimulating Hormone
    8. Serum Carbamazepine level