Expiration dating changes for lithium carbonate

Solvay waits for FDA approval

There is a temporary reduction in expiration dating for lithium carbonate 300 mg slow-release tablets (Lithobid) from Solvay Pharmaceuticals in Houston.

Solvay says it lost its original source of lithium carbonate but has identified and tested lithium carbonate from a new source. The company is now waiting for evaluation and approval from the Food and Drug Administration, which routinely reviews any changes affecting raw materials for prescription drugs. That FDA review includes assessment of quality data supporting the shelf-life of drug products made using the raw materials.

Limited data are available about the lithium carbonate used in Lithobid tablets. To avoid a shortage of Lithobid tablets, the FDA is not restricting distribution of the tablets prior to availability of full stability information. The FDA requires that new Lithobid tablets carry shorter, provisional expiration dates of six months, while longer-term data are acquired and evaluated.

FDA suggestions

Because the potential for depletion of stock still remains, Solvay and the FDA recommend that health care practitioners:

• limit prescriptions of lithium carbonate (Lithobid tablets) to quantities of no more than 30 days;
• be aware of alternative medications and/or other formulations of lithium to treat manic depressive illness;
• be aware that, as with any lithium formulation, it is important to closely monitor blood levels when initiating and changing therapeutic regimens.

Solvay officials say the company is collecting additional stability data and expects product expiration dating to be extended.

(Editor’s note: For additional information, call Solvay customer service at (800) 241-1643 or go to the FDA’s Web site at www.fda.gov/medwatch/safety/ 2000/lithob.htm.)