The active ingredient in Propecia, a baldness remedy approved by the Food and Drug Administration in 1997, is showing new promise as a way to prevent some prostate cancers. AP hide caption

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When dealing with aches and pains, sometimes the best way to get better is to feel better — and fast. Some popular medicines of old favored additives like cocaine. Courtesy of the National Library of Medicine hide caption

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How does the doctor decide what to write on the prescription pad? iStockphoto.com hide caption

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The Centers for Disease Control and Prevention says doctors should prescribe Truvada, a once-a-day pill for HIV, to help prevent infections in IV drug users. Jeff Chiu/AP hide caption

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Expensive prescriptions drugs can stretch people's finances, even if they have insurance. iStockphoto.com hide caption

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