Elizabeth Lee Vliet, who has an Arizona-based internal medicine practice, says she tries to ask very specific questions, particularly about over-the-counter medicine usage.

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Tax breaks for over-the-counter drugs date to 2003, as popular drugs like the allergy medicine Claritin began switching to over-the-counter status.

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Cough syrup, which is sold as an over-the-counter medicine, is sometimes used by addicts to get high, police say.

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Claritin, an allergy pill that was once a blockbuster, is now an over-the-counter medicine that could soon face even more generic competitors.

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"As the father of two daughters, I think it is important for us to make sure that we apply some common sense to various rules when it comes to over-the-counter medicine, " Obama said in 2011 when he endorsed Sebelius' decision.

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One mother of two who did not wish to be identified used the over-the-counter allergy and motion-sickness medicine Phenergan for a recent flight from Australia to the US. She said the first eight hours of the flight were "agony" and that she used the medication as a last resort to help her three-year-old daughter sleep.

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Is there a generic or over-the-counter alternative to the medicine you're prescribing me?

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There are four possible divisions that Pfizer could spin off: baby formula, over-the-counter products, veterinary medicine, and established products, which includes generic drugs.

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The medicine, called tranexamic acid, is sold over the counter under the brand names Cyklo-F and Femstrual to help women affected by heavy periods.

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