You can put another one in the "overly cautious" column for the Food and Drug Administration's new safety initiative.

The latest victim of unwarranted bad press: Pfizer's (NYSE:PFE) and Boehringer Ingelheim's Spiriva. After warning in March 2008 that the treatment for chronic obstructive pulmonary disease (COPD) might increase the risk of stroke, the FDA said yesterday that there's no evidence of any such association.

Spiriva competes with GlaxoSmithKline's (NYSE:GSK) Advair, Foradil from Merck (NYSE:MRK) and Novartis (NYSE:NVS), and AstraZeneca's (NYSE:AZN) Symbicort in the COPD market. With Spiriva sales of about $3 billion in 2008, the drug is clearly important to both Pfizer and Boehringer, and having the agency's investigation hanging over their heads certainly hasn't helped sales any.

Obviously, the FDA can't just ignore potential safety issues, but it seems that quite a few investigations come back with the agency concluding that nothing needs to change about doctors' prescribing habits. The FDA drew a similar conclusion for Merck's cholesterol drugs last month.

In fairness to the FDA, it calls the first report an "early communication," which does sound rather preliminary. The problem is that the press picks up on the warnings and treats them as near-facts -- especially in the headlines -- resulting in potential loss of sales.

The ideal situation for drug companies and their investors would be for the agency to hold off on saying anything until it was certain about changes to the label. But then the FDA would get in trouble with patients for not warning early enough when drugs really do have adverse side effects.

I guess we should just be happy that the FDA gets it right. Eventually.

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. Novartis is a Global Gains recommendation. The Fool owns shares of GlaxoSmithKline and has a disclosure policy.