LOUISVILLE, Ky. (WDRB) -- A secondhand market for medical supplies has local pharmacists concerned about the risks to patients.

Buyers have been advertising on telephone poles throughout Louisville, trying to resell diabetic testing strips online at discounted prices.

The practice is not necessarily illegal, as long as people do not commit Medicare, Medicaid or insurance fraud with the transaction.

"Test strips can be sensitive to light, humidity and temperature so ... if anything were ever to affect the integrity of the product, there definitely could be a safety concern," said Maggie Mangino, an assistant pharmacist with Norton Healthcare.

Pharmacists warn expired testing strips can also lead to inaccurate results.

“You wouldn’t know exactly what your glucose level was at," said Bradley Hall, a diabetic patient. "It could be dangerous. You could take too much medicine or not enough."

Hall tests his blood sugar levels three times a day and says it can get very expensive, especially when he is without insurance.

Prices vary depending on brand. Some medical supply companies sell strips for more than $160 without insurance for 100 strips. As a result, many people switch to a more affordable brand when cost is an issue. But even that can be expensive.

"There are places online that you can sell your strips for a substantial amount less," Hal. said. 

If cost is still a concern, patients can learn about special programs for people in need from their doctor.

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