It's no secret that you can save a lot of money in the drugstore by buying the generic equivalents of brand-name over-the-counter drugs. The trick is making sure you get the same drug to treat your symptoms.

It's not that hard -- you just have to know the active ingredient in the product.

Do you pay brand-name prices for Benadryl, when you can buy its active ingredient, diphenhydramine, for at least 25 percent less? When it comes to nonprescription drugs, you can save a ton of money by shopping around if you know the brand-name drug's active ingredient.

To find out just what's in that over-the-counter drug, run your cursor over the figure below. Pop-up boxes will identify the active ingredient in many popular name-brand drugs.

See "Comparing the cost of drugs" for price comparisons.

Comparing drug costs

Run your cursor over the figure below to view what active ingredients can be found in various brand-name drugs.