Ortho-McNeil-Janssen, a subsidiary of Johnson & Johnson, initiated a voluntary recall of its antipsychotic medication Risperdal because of an unusual odor. The recall covers one lot of 3-mg Risperdal tablets and one lot of 2-mg risperdone tablets. Risperdone is a generic form of the drug. The Risperdal lot originally contained 16,000 bottles, but the company believes approximately 1600 remain on the market, and believes around 1200 of the original 24,000 risperdone bottles remain. The lot numbers associated with the recall can be found in the company press release.

The odor is caused by small amounts of TBA (2,4,6 tribromoanisole), a chemical associated with preservatives applied to wood and found in shipping pallets used for storing and shipping drugs. TBA is not thought to be toxic, but it produces a musty, moldy odor, and a small number of people has reported temporary gastrointestinal symptoms after exposure to the smell.

This event marks the latest in a string of recalls resulting from odors caused by TBA contamination. Lots of J&J’s anti-HIV drug Prezista were recalled in May, and lots of their anticonvulsant Topomax were recalled in April. The company has been working since January 2010 to minimize the risks of further contamination and now requires suppliers to certify that they do not use pallets made from chemically treated wood.