Naprelan (naproxen sodium) is the once-a-day formulation of the arthritis medication Naprosyn (naproxen). Naprelan, a sodium salt formulation of Naprosyn, provides for more rapid absorption.

Naprelan tablets use a proprietary delivery system, IPDAS (Intestinal Protective Drug Absorption System), a matrix of naproxen sodium with immediate and controlled release components. Upon ingestion, and after rapid disintegration of the tablet matrix, an initial fraction (approximately 30%) of the medication is released for rapid systemic absorption achieving onset of analgesic action within 30 minutes. In addition, a sustained-release component of microparticles provide an extended absorption phase that both minimizes local gastrointestinal concentrations and prolongs therapeutic systemic levels of the drug, enabling 24-hour duration of action and once-a-day dosing (2-4).

The most frequent complaints relate to the gastrointestinal tract. In subjects treated chronically with Naprelan, a non-steroidal anti-inflammatory drug, serious gastrointestinal toxicity such as perforation, ulceration, and bleeding can occur.

Cooper, SA, Gaston, G, Devane J. A double-blind, randomized, parallel, group study of the acute analgesic efficacy of Naprelan in patients following oral surgery. February 1994. Data on file, Wyeth-Ayerst Laboratories.

A double-blind, randomized, parallel, group study of the acute analgesic efficacy of Naprelan. December 1994. Data on file, Wyeth-Ayerst Laboratories.

Caldwell, J. Keller M. A Comparison of Naprelan versus Naprosyn in the treatment of rheumatoid arthritis. December 1994. Data on file, Wyeth-Ayerst Laboratories.

Serge E. Long term experience with naproxen: Open label cohort survey of nearly 900 rheumatoid arthritis and osteoarthritis patients. Current Ther. Res 1980; 28:47-60.

Naproxen or naproxen sodium-based products account for approximately one in every five prescriptions written for non-steroidal anti-inflammatory drugs in the United States.