Fewer fill "dispense as written" prescriptions - study

* Practice may be costing health system $8 bln/year-study

* Some generics available for one-third cost of brands

* Some doctors still concerned about generics

By Genevra Pittman

NEW YORK (Reuters Health) - Patients are less likely to fill prescriptions when their doctors specify that brand name drugs can't be substituted with generics, according to a new study.

Along with leaving patients without their medications, the practice could be costing the health system almost $8 billion a year, the authors of the study in the American Journal of Medicine calculated. (bit.ly/eZZjHh)

Despite evidence that generic drugs work just as well and are just as safe as brand name drugs, "there's a small population of doctors that still express concern about generics," Dr. William Shrank, the lead author of the study from Harvard Medical School in Boston told Reuters Health.

And, Shrank added, "it's really hard for either patients or doctors to anticipate the cost of the medication when the patient goes to the pharmacy."

During the health care reform debate, policymakers have been pushing for widespread use of generic drugs, which in some cases may be available for as little as one-third of the price of brand name drugs.

However, doctors are able to prevent pharmacies from giving patients generic drugs by writing "dispense as written" on a prescription.

Patients can also request brand name drugs themselves.

In the study, Shrank and his colleagues analyzed all prescriptions that were filled by CVS Caremark (CVS.N) at CVS stores and online over the course of 1 month.

In total, 5.6 million prescriptions were filled by 2 million patients. CVS Caremark funded the study.

Almost 3 percent of prescriptions were labeled "dispense as written" by doctors, and another 2 percent were marked by patients who wanted brand name drugs.

"THINK VERY CAREFULLY"

But even when patients were the ones who had requested a brand name drug, they were less likely to fill the prescription when they couldn't substitute generics.

When there was no "dispense as written" label on a new prescription for patients with chronic disease, about 8 percent went unfilled. That compared to close to 12 percent when patients themselves said they didn't want a generic.

Older patients and doctors were both more likely to require that a prescription be filled with brand name drugs.

When the authors scaled the results to the 3.6 billion prescriptions that are filled annually in the United States, Shrank and his colleagues found that patients could save $1.2 billion if doctors did away with "dispense as written" -- and the health system could save $7.7 billion.

The findings show that "it's important that physicians think very carefully about whether or not the patient needs that particular brand of medication," Dr. Alex Federman, of the Mount Sinai School of Medicine in New York City, told Reuters Health.

"And, they've got to keep working that message about generics as being a perfectly cost-effective substitute for brand name medications," said Federman, who has studied how people use generics but was not involved in the report.

Shrank said that while some doctors and patients may like the idea of prescribing and taking brand name drugs, patients might not realize how much extra those drugs will cost them.

He and his colleagues found that patients in the study paid an average of about $18 for a generic prescription and $44.50 for brand name drugs that had a generic alternative.

Knowing that beforehand might help both doctors and patients make more educated decisions, Shrank said.

"There has to be more open discussion between doctors and patients about medication costs (because) cost ends up being an important barrier for many patients," he said.