WASHINGTON (AP) -- Worried parents are bombarding drugmaker Abbott Laboratories with phone calls about millions of containers of infant formula recalled because they might contain parts of beetles.

But North Chicago, Ill.-based Abbott says it recalled the 5 million cans of Similac powdered formula only as a precaution, and it's unlikely any product sold is contaminated.

Doctors also say chances for serious illness are slim in babies who drink formula containing bug parts.

Still, parents like Stephanie Roseman of Farmington Hills, Mich., are upset.

She said on Thursday that her 3-month-old son seemed like he had a stomach ache this week. So Roseman is switching to a rival formula.

Abbott says it uncovered the insects last week at a manufacturing plant in Sturgis, Mich.

Click here to see if Simlac you purchased is part of the recall 

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