A new study out of Australia shows a worrying increase in accidental overdoses of methotrexate, a drug commonly used to treat rheumatoid arthritis (RA).
Methotrexate is an immunosuppressant drug originally developed as chemotherapy for leukemia and other cancers. Smaller doses also proved to offer effective treatment for RA, and since the 1990s it has become the gold standard. It is administered weekly, either in tablets or injection form. Methotrexate often is prescribed with folic acid to combat side effects, such as potential hair loss. Individuals taking this medication also may be prescribed prednisone.
Accidental overdoses of methotrexate
The study published in the Medical Journal of Australia found that since the year 2000, 22 deaths in Australia have been associated with methotrexate. Additional data from the NSW Poison Information Centre showed a rise especially between the years of 2014-2015. The deaths appear to be related to accidental overdoses.
Data from other sources show a total of 91 cases of serious incorrect dosing resulting in hospitalization. In these cases, people took methotrexate on a daily basis, rather than once a week. Doing this for just three days can result in life-threatening toxicity. Higher or more frequent doses of methotrexate can result in liver toxicity, gastrointestinal mucosal ulceration, sepsis, and death.
The ages of the individuals who died ranged from 66-87. Age-related vision loss and memory issues likely contributed to the dosing errors: methotrexate tablets are small and resemble many other types of medication.
The U.S. connection
A study of errors reported over four years to the U.S. Food and Drug Administration (FDA) showed that these accidental overdoses happen in North America as well, most commonly due to confusion about the weekly dose. The data show more than 100 dosing errors resulted in 25 deaths.
This study examined the origin of the mistakes in more detail. The prescriber was responsible for 37 percent of errors; the patient for 20 percent; dispensing of the drug 19 percent; and 17 percent of dosing errors were attributed to the administration of the medication by a health care professional.
What you can do to stay safe
When prescribed and taken correctly, methotrexate is safe and can be very effective in treating RA. The number of deaths overall is quite small when looking at the big picture and how many people take this drug for RA and other autoimmune diseases. Nonetheless, the news of these accidental overdoses should be taken seriously.
There are precautions you can take to make sure that you stay safe when taking methotrexate.
*It starts at your doctor’s office with a discussion about how to take your tablets or injections. Next, make sure you talk to your pharmacist and check that they have dispensed the drug with the same instructions as your doctor’s prescription.
*If you are taking methotrexate in tablet form, pay close attention to what they look like. They are usually small and round, with a yellowish color. If you use a pill container that has multiple compartments for different days and times, make sure that you only put your methotrexate tablets in one slot. You may also wish to write a reminder in your calendar or set an alarm on your phone for your once-a-week dose.
*When you have a routine of taking medication, it can become second nature to take your pills. It’s easy to forget if you’ve taken your medication. This can be compounded by the brain fog that often accompanies RA and chronic pain. To avoid a double dose, make a note in your calendar when you have taken your weekly methotrexate. If you’re using injectable methotrexate, put a Band-Aid on the injection site. Not only does it protect the site, but it also serves as a visual reminder that you have indeed taken your medication that week.
Medication is a tool you use to manage your RA, much the same way that a kitchen knife is a tool you use to prepare dinner. Like the knife, meds can have a sharp edge and it’s important to treat them with respect. That means learning how to use the medication by asking your doctor to provide you with the education and information you need. As well, it’s important to pay attention as you use it in your home. If you are careful, you will be able to use it safely.