When it comes to prescription drugs, it really does pay to shop around.
A study of prices for drugs commonly taken by diabetes patients showed that mail-order retailers and big-box discounters can save consumers thousands of dollars a year compared to the local pharmacy.
Overall, Medco by Mail and Wal-Mart were the least expensive, while neighborhood and chain pharmacies generally charged the most, according to Dr. Clifton Jackness and Dr. Ronald Tamler, both of the Mount Sinai School of Medicine in New York City.
"Being an informed consumer is clearly beneficial," they told colleagues at the American Diabetes Association meeting.
The total monthly out-of-pocket price for all 10 drugs most commonly prescribed to diabetes patients for any indication ranged from a low of $428.35 with Medco to a high of $641.90 with Rite Aid.
The researchers said lower prices may encourage patients to stick with their medications and stay healthier, since nearly one in five adults with diabetes reports cutting back on their prescriptions because of cost.
However, there is often a tradeoff for lower prices, said Dr. Paul Robertson, ADA's president of medicine and science.
"Pharmacies, especially local ones, offer more than drugs," he said. "They offer service and the opportunity to talk to a pharmacist."
Giving that up in exchange for a lower bill might be worthwhile for some patients who are on a stable regimen and familiar with their medications, whereas for others it might not, Robertson noted.
The stakes in shopping around are collectively enormous. According to the American Diabetes Association, there are 23.6 million diabetics in the United States, or 8 percent of the population. And their number is growing as the nation ages and unhealthy lifestyles lead to an increase in diabetes diagnoses.
To calculate the impact of shopping around, the researchers tabulated the most common prescriptions filled by diabetes patients under age 65 -- a population expected to have at least some out-of-pocket cost associated with their medications -- from a database compiled by 91 health insurance plans across the United States.
After excluding non-chronic medications such as antibiotics, the top medications in order of number of prescriptions were:
Lisinopril (Prinivil, Zestril)
Rosiglitazone (Avandia), excluded from the analysis because of declining use since the time covered by the database
Furosemide (Lasix, Furocot)
Insulin glargine (Lantus)
Interestingly, the list contained several drugs that were not strictly diabetes-related, including statins that fight cholesterol and medications to lower blood pressure.
Jackness noted that diabetes patients take an average of 8.9 medications, and believes the typical patient would be on the majority of drugs on the list, he said.
The cost of a 30-day supply of each -- assuming no prescription drug coverage by public or private insurance -- was determined from price data collected by the New York and New Jersey State Attorneys General.