When your health condition changes, or when new treatments become available, your healthcare providers may recommend changes to your medicines. If this happens, it’s important to know whether the changes affect the use of other medicines you are already taking. It’s also important to make other healthcare providers aware of the changes. Often, you will be the best person to communicate these changes.
Our sister organization in Canada recently received a report about a patient mistakenly given two different medicines to treat the same problem. The patient’s doctor prescribed a new medicine to replace an existing one, but the new medicine was dispensed and eventually taken in addition to the existing one. One of the drugs was Coumadin (warfarin), a blood thinner for preventing blood clots. The patient’s family doctor wanted the consumer to start taking a different blood thinner instead, a medicine called dabigatran (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 patient to stop taking the warfarin and the hematoma eventually improved.
Actually, this patient was pretty lucky. The main side effect of each of these drugs alone is excessive bleeding. Taking the two blood thinners together like this is particularly dangerous and easily may have caused severe internal bleeding, like bleeding in the brain if the patient happens to fall and have a head injury. Severe bleeding can be fatal if it isn’t treated in time.