Dropping the prescription requirement for a drug usually means the price comes down and people can treat themselves for common ailments without seeing the doctor. But it can also mean paying more for the drug and facing the danger of misdiagnosing themselves.

The question of moving drugs from prescription to over-the-counter sales is "a complicated issue that needs to be dealt with on a case-by-case basis," said Dr. Sidney Wolfe of Public Citizen Health Research Group.

It's a balancing act pitting potential health benefits against possible dangers. And it's a decision that involves millions of dollars changing hands among the sometimes conflicting interests of consumers, drug makers and insurance companies.

Studies find many consumers want to treat themselves with nonprescription drugs when possible and an increasing number of drugs once available only with a doctor's approval now are jostling for shelf space in drug stores and supermarkets.

When a drug is switched to over-the-counter sales, the price usually decreases. But whether that's a good thing for users can depend on whether they have insurance.

Insurers generally don't cover nonprescription drugs, so selling more of them that way is good for the industry, said Linda Simoni-Wastila, a pharmacy professor at the University of Maryland in Baltimore. And the use of such drugs without a doctor's oversight can mask medical complications, she added.

More active role

Linda Golodner, president of the National Consumers League, said consumers are taking a more active role in their health care, even self-diagnosing and medicating.

A survey commissioned by her group found that consumers generally like over-the-counter drugs and use them regularly to treat minor health conditions. But one-third of consumers don't regularly read the labels before purchasing or using them, Golodner added.

According to a paper published by the American Academy of Family Physicians, nonprescription drugs account for about 60 percent of all drugs sold in the United States and are used to treat about 400 ailments.

Former prescription drugs now sold over the counter include painkillers Aleve, Motrin and Advil; heartburn drugs Zantac, Tagamet, Axid and Pepcid; and cold and allergy drugs Tavist-1 and Nasalcrom. Also on the list are the anti-fungal drugs Gyne-Lotrimin, Femstat and Monistat, baldness treatment Rogaine and smoking deterrents Nicotrol, NicoDerm and Nicorette.

Many more drugs could be considered for over-the-counter sale, such as the "morning after" pill that women need in a hurry to prevent pregnancy and vaginal "microbicides" that companies are developing to protect against AIDS.

The switch can have positive results. Take, for example, the nicotine patch and gum to help people quit smoking.

In 1996, the products became available over the counter and about 6 million people used them, double the sales of the year before. Within two years it was 9 million.