Odd odor prompts drug recall -- again

An unusual smell from tablets of Topamax, an anti-seizure drug, has prompted Ortho-McNeil, part of Johnson & Johnson, to recall 57,000 bottles of the drug.

The company said four consumers reported an “uncharacteristic odor” thought to be caused by trace amounts of TBA, a byproduct from a chemical used in treating wood. The TBA may have come from the wood pallets on which the medication is shipped and stored. The company is recalling two shipments from October and December 2010.

This particular recall applies to 100-milligram tablets of Topamax in bottles of 60 tablets with expiration-date markings of 06-2012 and 09-2012.

Although the company didn’t describe the smell from TBA, known to chemists as 2,4,6-tribromoanisole, the Food and Drug Administration describes it in a Q&A on good manufacturing practices:

“Reports, including some dating back several decades, describe a moldy or musty odor in food (and wine) products due to contamination with trace amounts of halogenated anisole compounds such as 2,4,6-tribromoanisole (TBA).”

Companies and consumers would seem to be increasingly aware of the smell. Pfizer recalled a lot of Lipitor in December for the same problem. And early last year, McNeil Consumer Healthcare recalled a plethora of over-the-counter products because of, yes, “an unusual moldy, musty or mildew-like odor.” Again, TBA was blamed.

It appears that certain fungi convert a common wood preservative, TBP, into TBA, resulting in the tell-tale odor.

Such contamination creates the smell but leads to only “minimal health risks, the FDA says, adding that a few patients reported gastrointestinal symptoms.

The FDA recommends that manufacturers not store drug products near wood treated by halogenated phenolic preservative -- something J&J stated it asked its suppliers in January 2010 to verify.

But perhaps a better screening tool is the human nose. The FDA says odor from TBA can be detected by consumers even at the level of parts per billion or less.