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SafeMedicationUse Newsletter

An Important Question - Does this new medicine replace one of my current medicines?


When your health condition changes, or when new treatments become available, your healthcare providers may recommend changes to your medicines. If this happens, it is important to know whether the changes affect the use of other medicines you are taking. It is also important to make other healthcare providers aware of the changes. Often, you will be the person best able to communicate these changes to your various care providers. has received a report about a consumer who was mistakenly given two different medicines to treat the same problem. The consumer's doctor prescribed a new medicine to replace an existing medicine, but the new medicine was dispensed and taken in addition to the existing medicine. The consumer had been taking warfarin, a blood thinner that is used to prevent or treat conditions caused by blood clots. The consumer's family doctor wanted the consumer to start taking a different blood thinner instead, a medicine called dabigatran (previously known by the brand name Pradax and now changed to Pradaxa). Two months later, the consumer was planning a cruise vacation and asked the pharmacy to provide refills for several medicines. The pharmacy gave the consumer refills for both the warfarin and the dabigatran, and the consumer took both medicines for 5 days. During the cruise, the consumer noticed that one leg had become dark and swollen. The ship's doctor diagnosed a severe hematoma (a collection of blood under the skin) that was caused by the use of the two blood thinners together. The ship's doctor advised the consumer to stop taking the warfarin, as the family doctor had originally intended, and the hematoma eventually improved. has the following advice for preventing mistakes like this one:

  • If a healthcare provider prescribes a new medicine, be sure to ask whether it replaces another medicine or changes the way you take another medicine.
  • If a healthcare provider advises you to stop taking a medicine, be sure to let your pharmacist know. This will help ensure that your records at the pharmacy are kept up to date.
  • Be specific when requesting refills of prescription medicines. Provide both the prescription number and the name for each medicine you require.
  • Keep a list of your medicines and carry it with you at all times. Bring it with you any time you access healthcare, and update it every time there is a change to your medicines. You can also ask the healthcare provider to help you make the necessary changes on your list of medicines.
  • Whenever you pick up medicines at the pharmacy, check your prescriptions. Make sure that you have received the medicines that you are expecting. It may be helpful to compare the prescription containers you receive from the pharmacy against your list of medicines. If there are unexpected differences between the containers you receive and your list, speak with a pharmacy staff member.
  • Know the reason you are taking each of your medicines. Knowing the reason for each medicine can help you understand if you are supposed to be taking more than one medicine for the same reason or if a mistake has been made.
  • If a healthcare provider instructs you to change the way you are taking a medicine, including stopping a medicine altogether, be sure to get the new instructions in writing. If you receive new instructions by telephone, write them down and repeat them back before hanging up the phone.
  • Always read any printed material that you receive with your medicine. This often includes information about medicines that may interact with each other, as well as information about possible side effects. If there is anything you do not understand, speak with your pharmacist.

Tips for Healthcare Practitioners

The following steps can help prevent misunderstandings when one medicine is being replaced by a new medicine:

  • Review all changes with patients and ask for feedback to make sure they understand the new instructions.
  • Ensure that changes made to patients' medicines are communicated to other healthcare providers. When writing prescriptions for medicines that are intended to replace other medicines, include written information as to which medicines are to be discontinued.
  • Update patient records to ensure that discontinued medicines are removed from lists of active treatments.
  • Assist patients to update their lists of medicines.
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