Utah's frigid temperatures are posing a hidden hazard to the health of its citizens.

The Utah Pharmaceutical Association warns that the cold weather could be playing havoc with prescription drugs - especially those ordered through the mail."The cold, particularly freezing, can change the mechanism of the drug - making it ineffective," said C. Neil Jensen, association executive director. "Freezing can break down chemicals and other ingredients in the products, making them potentially harmful to patients."

Of particular concern to local pharmacists are prescriptions obtained by Utahns from out-of-state, mail-order pharmacies. An increasing number of local insurance companies are promoting mail orders, especially for maintenance drugs. The American Association of Retired Persons, in fact, operates the nation's biggest mail-order drug business.

These out-of-state, mail-order pharmacies have raised the ire of local pharmacists who have long argued that pranksters can steal drugs from mailboxes.

They now warn that the box poses another threat. There's no way for a patient to determine if a drug that has been sitting in a mailbox has broken down from improper storage.

"In the shipment and in the mailbox, the product often freezes and then doesn't have the same potency," Jensen said. "This could cause a diabetic patient serious problems due to an impotency of the insulin."

More than one Utah pharmacist has been approached by a panicked customer, carrying a frozen bottle of insulin.

Use caution if the medication has been exposed to severe heat or cold is Jensen's recommendation.

"If you have any questions, you should consult your local pharmacist to be sure that your medications have not been affected by the freezing temperatures that have beset Utah recently," he said.