Diabetes Disaster Averted #62: 'Double Dosage'

It turns out that when he saw the endocrinologist, it was in the city where he worked and he had gone to the pharmacy there to have the Glucophage XR filled using his insurance pharmacy card. He had received the prescription for the metformin from his primary care provider, and paid for it at a chain pharmacy near his home, which offered $10 copayments for generic drugs. (He stated this was less than his copayment through insurance.)

Multiple safety checks had missed this over-dosage of medication. First, the patient did not provide an adequate history of his medications to the endocrinologist. All patients should carry an up-dated medication list with them when they go to their health care providers. There was inadequate communication between the PCP and the endocrinologist, in both directions. Referrals to specialty should include a current medication list, rather than to only depend on patient-provided information. Patients should be encouraged to only fill medications that they take on a regular basis at one pharmacy, or pharmacy chain. In this case the 'double-dosage' of metformin would have been picked up by the pharmacy's computer system and would have averted this problem.

Lesson Learned:

It is very important to make sure that you have a complete medication history when you meet with your patients. Sometimes it is effective to ask, "How many pills are you taking in the morning (at lunch, at dinner, at bedtime, etc…)?" If the number of pills doesn't equal the medications by dose of their reported medication list, it's time to delve further into the issue.

Laurie Porcaro, RN, CDE