Published February 1, 2017 (revised June 24, 2024)
When your health condition changes, or when new treatments become available, your doctor 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. If you are seeing several healthcare providers, they may not be sharing updated information about your medicines. That is why you will be the best person to communicate these changes to your various healthcare providers.
This includes letting all the pharmacies you use know about prescription changes so they can detect if your medicines react with each other and so you don’t continue to receive refills of a medicine that has been stopped or changed by your doctor. This is also important if you have signed up for automatic or courtesy refills. Once you sign up for this service, all your prescriptions for ongoing medicines are automatically refilled until there are no more refills left. This may happen even if you have been told to stop taking the medicine or if your doctor recently changed the dose or how often you take the medicine.
Consider these examples of potentially dangerous events that led to taking, or almost taking, medicines that were no longer prescribed.
Case 1: Taking two different blood thinners
A woman was mistakenly taking two different medicines to treat the same problem. Her family 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 warfarin (once know as the brand name Coumadin), a blood thinner for preventing blood clots. The woman’s doctor wanted her to stop taking the warfarin and start taking a different blood thinner, dabigatran (Pradaxa).
Two months later, the woman was planning a cruise vacation and asked the pharmacy to provide refills for several medicines. The pharmacy gave her refills for both the warfarin and the dabigatran. The woman took both medicines for 5 days. During the cruise, the woman noticed that one leg had become dark and swollen. The ship’s doctor told her she had a severe hematoma (a collection of blood under the skin) that was caused by taking the two blood thinners together. The ship’s doctor advised the woman to stop taking the warfarin, as the family doctor had originally intended. The hematoma eventually improved.
The woman was lucky. Taking the two blood thinners together could have caused much more severe bleeding. Severe bleeding can be fatal if it isn’t immediately treated.
Case 2: Taking two different doses of a heart medicine
An elderly man taking diltiazem to treat angina (chest pain) received a new prescription from his doctor. The doctor increased the dose of diltiazem extended release (ER) from 240 mg to 360 mg. The man went to the pharmacy to fill the new prescription. He also picked up refills on prescriptions that he had called into the pharmacy the previous day, before his doctor’s appointment. One of those prescriptions was for diltiazem ER 240 mg, which was his old prescription that still had refills on it.
When the man got home, he initially failed to notice that he had two prescriptions for the same medicine. After taking both medicines for about a week, he finally noticed the problem and called the pharmacy to see if there was a mistake. The pharmacist contacted the doctor to determine which dose the man should take. The man was told to take the higher dose and to return the other prescription to the pharmacy. Had the man continued to take both doses of the diltiazem, he could have experienced serious heart irregularities.
Case 3: Almost taking a discontinued blood pressure medicine
A pharmacy called a man to pick up his prescriptions that had been automatically refilled. After he picked up the medicines and drove home, he remembered that his doctor told him to stop taking one of the medicines, amlodipine, which was used to treat high blood pressure. His blood pressure was very low during his recent physical exam, so his doctor wanted him to stop taking the medicine until his next office visit. The pharmacist did not know the medicine had been stopped, so the prescription was automatically refilled.
Fortunately, the man remembered not to take the medicine and called the pharmacy to let the pharmacist know. Had he taken the medicine, he could have experienced dizziness and fallen or been involved in an accident from a dangerously low blood pressure.
Here's what you can do: Follow these suggestions for what to do if your doctor prescribes a new medicine that may replace one of your current medicines, how to stay safe when using automatic refill services, and how to avoid taking prescription medicines that are no longer prescribed by your doctor.
Verify with your doctor. If a doctor prescribes a new medicine, be sure to ask whether it replaces another medicine you already take or if it will interfere or change the way you take any of your medicines.
Get new instructions in writing. If a doctor instructs you to change the way you are taking a medicine, including stopping a medicine altogether, get the new instructions in writing. If a new prescription will be sent to your pharmacy electronically, ask for a copy or written information about the new prescription on your summary of your office visit. If you receive new instructions by telephone, write them down and repeat them back before hanging up the phone.
Keep a current list of medicines. 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.
Keep your pharmacist informed. Notify your pharmacist of any changes made to the prescription medicines you take. This includes medicines that are stopped, doses that are increased or decreased, and changes in how often you take the medicine. This will help ensure that your records at the pharmacy are kept up to date.
Discard old medicines. If your doctor tells you to stop taking a prescription medicine, dispose of it properly to lessen the risk of confusion.
Bring in your old medicine. If you have a new prescription because your doctor changed the dose or directions for taking the medicine, you should dispose of the old medicine to prevent confusion. Check with your pharmacy or township to see when they are holding a Prescription Drug Take-Back event so you can drop off your unused medicines for proper disposal.
Check your medicines before leaving the pharmacy. When you pick up medicines at the pharmacy, check them before you leave. Make sure they have your name on the label and that you 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 pharmacist.
Check for duplicate medicines. When you get home with your medicine (or when medicine is delivered to your home), look at all your prescription medicines together to make sure you do not have duplicates. Remaining supplies of refilled medicines are expected. To avoid double dosing, set aside the new container of medicine until you finish the medicine in the old container. Make sure the newly purchased medicine is not the same as another medicine on hand in a different dose or with different directions. If you have brand-name medicines, check the generic name of the medicine on the prescription label to make sure you do not have duplicate medicines.
Use the same pharmacy. Try to fill all your prescriptions at the same pharmacy. This way, all your prescription information will be available to the pharmacist, and it will be easier to keep the pharmacist informed of any changes in your prescribed medicines.
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.
