Substitutions can be Sticky


When a middle-aged man arrived at a pharmacy to pick up a refill for lactulose (a common laxative), he was told that he needed a new prescription from his doctor. There were no refills left on his previous prescription. The pharmacist suggested that the man could use KARO corn syrup as a substitute for lactulose until he visited his doctor for his next check-up.

(Karo corn syrup is an age-old remedy sometimes used for constipation in children and adults.) But the man was taking lactulose to treat a liver problem, not constipation. Luckily, the patient called his doctor about the suggestion and was told not to use the substitute. He was given a new prescription for lactulose. The risk of substituting the prescription medicine with Karo corn syrup could have been very serious because untreated liver problems can sometimes lead to mental confusion and even coma. You need to call your doctor if your pharmacist gives you a generic substitute of the medicine; generic medicines contain the same ingredients as brand medicines. But if a totally different medicine or product is suggested, you may want to first check with your doctor before making the switch. Also ask your doctor to write the reason you are taking a medicine on the prescription. This way, the pharmacist will be able to make more accurate suggestions. The suggestion to use Karo syrup would not have been wrong if the man had been using lactulose to treat constipation.

Created on July 1, 2007

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