Pregabalin: An antiepileptic agent useful for neuropathic pain

Purpose. The pharmacology, pharmacokinetics, clinical efficacy, adverse effects, and dosage and administration of pregabalin are reviewed. Summary. Pregabalin is the first drug to receive approved labeling from the Food and Drug Administration (FDA) for the treatment of painful diabetic neuropathy and postherpetic neuralgia and is the first antiepileptic agent to receive FDA-approved labeling since 1999. Pregabalin is the pharmacologically active S-enantiomer of racemic 3-isobutyl gamma-aminobutyric acid. Pregabalin has demonstrated efficacy in the management of neuropathic pain associated with diabetic peripheral neuropathy, postherpetic neuralgia, and as adjunctive therapy for adult patients with partial onset seizures. Its exact mechanism of action is unknown. Pregabalin is rapidly absorbed and exhibits linear pharmacokinetics after oral administration. The lack of hepatic metabolism and lack of interaction with cytochrome P-450 isoenzymes explain the absence of drug interactions with pregabalin. Several clinical studies have demonstrated pregabalin's efficacy for each of the FDA-approved indications, with dizziness and somnolence reported as the most common adverse events. Pregabalin has been designated as a Schedule V controlled substance because of its potential for abuse and dependence. The starting dosage for patients with neuropathic pain associated with diabetic peripheral neuropathy is 50 mg three times daily and may be increased to 300 mg daily within one week based on efficacy and tolerability. The starting dosage for patients with partial-onset seizures is 75 mg twice daily or 50 mg three times daily and may be increased to 600 mg daily based on individual response and tolerability. Conclusion. Pregabalin may be beneficial for the treatment of neuropathic pain or partial-onset seizures in patients who do not respond to conventional treatments or cannot tolerate their adverse effects.