You may have several "double duty" drugs in your medicine cabinet, but drug companies often aren't allowed to tell you the multiple purposes of over-the-counter medications.

The federal Food and Drug Administration, in fact, limits the number of uses for which many of the drugs may be recommended."Most drugs are approved for a single indication," said C. Niel Jensen, executive director of the Utah Pharmaceutical Association. "A second approval from the FDA could take anywhere from nine to 10 years."

Meanwhile, however, professionals are enlightening patients.

"Physicians sense that drugs have secondary benefits and prescribe for such."

A good case in point is aspirin.

Recent studies conducted on some 22,071 male physicians showed that aspirin helped lower the risk of heart attacks by 47 percent in some men who had never previously suffered attacks, strokes or other serious illnesses.

Dennis White, president-elect of the Utah Pharmaceutical Association, said the reason aspirin works so well in some forms of cardiovascular treatment is because it makes the blood less likely to clot, actually thinning the blood.

Heart attacks usually occur when clots form in the coronary arteries, choking off the heart's own blood supply.

With this data in hand, aspirin manufacturers began hyping the tablets as the wonder drugs of the century. Sales increased 25 to 30 percent.

Then, the FDA stepped in. Aspirin manufacturers were told to keep the news about aspirin's possible effectiveness in preventing some heart attacks out of their ads.

The drug, they said, isn't without side effects.

"Because of the many uses and side effects of aspirin, it likely wouldn't be approved by the FDA today as an over-the-counter drug," Jensen said.

Other non-prescription drugs haven't been as highly publicized.

"People believe if it's over the counter, it's not any good - that they obviously aren't sick enough to warrant a prescription," White said. "Prescriptions are viewed as `magic dust.' If the doctor has written it and we pull it out from behind the counter, it's going to work better than if you tell a patient to go pick it up off the aisle."

Said White, "That doesn't necessarily mean they don't need the over-the-counter drug and that it is not going to help them."

Take Bendectin, for example. Bendectin, prescribed to treat nausea among pregnant women, was pulled off the market several years ago following a barrage of litigation.

Since then, however, a number of obstetricians, unconvinced of the drug's potential to cause fetal birth defects, have been advising women to instead purchase Unisom, an over-the-counter drug, and vitamin B6.

Bendectin, a prescription medication, included both drugs.

The pharmacists believe more and more drugs are going from prescription status to over the counter. Interest in over-the-counter, double-duty drugs, they say, is skyrocketing with increasing medical costs.

So how do you choose the drugs and medicines that are right for you?

Jensen suggests reading labels before you buy any product. If you aren't sure about the ingredients or don't understand the wording on a package, ask the pharmacist and not the people who stock the shelves or run the cash registers.

Before taking any kind of a drug, consult a physician or pharmacist to learn if the drug could have any adverse side effect.

"Use your pharmacists correctly - and make your pharmacists serve you correctly. You'll get much better treatment," Jensen said."

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Some multipurpose drugs that can be bought over the counter

-Psyllium, a soluble fiber also found in the laxative Metamucil, helps lower blood cholesterol levels by an average of 15 percent and adds fiber to the stomach.

-Antihistamines, which treat hay fever and cold symptoms, will also help you rest better at night because they may contain phenylpropanolamine hyrdochloride, an ingredient used in some sleeping pills. Antihistamines are also being used to treat some allergic reactions to bee stings.

-Antacids such as Rolaids or Tums can supply the body with calcium and boost the body's defenses against osteoroposis while relieving heartburn.

-A small dose of Milk of Magnesia will cure heartburn, but a larger dose will also act as a laxative because it also contains an antacid. Milk of Magnesia may also be used to rinse the inside of the mouth when painful canker sores are present.

-Castor oil, another household laxative, may also be applied to the scalp to treat dryness and reduce itching.

-Ibuprofen, released as Motrin, is used to treat pain and inflamation. It may also be used to lower fevers.