Pregnancy Risk Category C
How supplied
Capsules: 100 mg, 300 mg, 400 mg
Action
Unknown. Although structurally related to gamma-aminobutyric acid (GABA), drug doesn't interact with GABA receptors and isn't converted metabolically into GABA or a GABA agonist. It doesn't inhibit GABA reuptake and doesn't prevent degradation.
Indications & dosage
Adjunctive treatment of partial seizures with and without secondary generalization in adults with epilepsy--
Adults: initially, 300 mg P.O. h.s. on day 1; 300 mg P.O. b.i.d. on day 2; then 300 mg P.O. t.i.d. on day 3. Dosage increased as needed and tolerated to 1,800 mg daily in divided doses. Doses up to 3,600 mg daily have been well tolerated.
Adjust-a-dose: For patients with renal failure with creatinine clearance over 60 ml/minute, give 400 mg P.O. t.i.d.; if clearance is between 30 and 60 ml/
minute, 300 mg P.O. b.i.d.; between 15 and 30 ml/minute, 300 mg P.O. daily; and if clearance is under 15 ml/minute, 300 mg P.O. every other day. Patients on dialysis should receive a loading dose of 300 to 400 mg P.O.; then 200 to 300 mg P.O. q 4 hours during hemodialysis.
Adverse reactions
CNS: fatigue, somnolence, dizziness, ataxia, nystagmus, tremor, nervousness, dysarthria, amnesia, depression, abnormal thinking, twitching, incoordination.
CV: peripheral edema, vasodilation.
EENT: diplopia, rhinitis, pharyngitis, dry throat, coughing, amblyopia.
GI: nausea, vomiting, dyspepsia, dry mouth, constipation, increased appetite, dental abnormalities.
GU: impotence.
Hematologic: leukopenia.
Metabolic: weight gain.
Musculoskeletal: back pain, myalgia, fractures.
Skin: pruritus, abrasion.
Interactions
Drug-drug. Antacids: decreased absorption of gabapentin. Separate administration times by at least 2 hours.
Effects on diagnostic tests
Drug causes false-positive results with the Ames-N-Multistix SG dipstick test for urinary protein when added to other antiepileptic drugs. The more specific sulfosalicylic acid precipitation procedure is recommended to determine the presence of urine protein.
Contraindications
Contraindicated in patients with hypersensitivity to drug.
Nursing considerations
Patient teaching
*Liquid contains alcohol. **May contain tartrazine. †Canada ‡Australia §U.K. OTCOver the counter
Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE-THREATENING