- A new study has identified 24 common and potentially inappropriate medication cascades, which could result in medication-related harm in older adults.
- These prescribing chain reactions can occur when a drug side effect is mistaken for a new medical condition, leading to another medication being prescribed unnecessarily.
- Older adults may be particularly vulnerable as they are more likely to take multiple medications for several chronic conditions, making it harder to identify the original cause of a new symptom.
- Better medication reviews, clinical decision-support tools, and greater involvement of pharmacists could help clinicians to recognize potentially inappropriate prescribing cascades.
A prescribing cascade occurs when a medication causes a side effect that is mistaken for a new medical condition. Instead of identifying the original drug as the possible cause, a clinician may prescribe another medication to treat the new symptom.
For example, nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to manage pain and can increase blood pressure in some people. If this increase is interpreted as newly developed hypertension, a person may be prescribed a blood pressure-lowering medication rather than having their pain medication reassessed.
A large Ontario study has identified 24 potentially inappropriate prescribing cascades that may cause older adults to receive medications to treat side effects of drugs they are already taking.
The research, published in
The researchers describe these as potentially inappropriate prescribing cascades (PIPCs) when the additional medication may not be necessary or may expose the individual to avoidable harm.
The research highlights that older adults may be at a higher risk of PIPCs, as they are more likely to take several medications at the same time due to living with multiple chronic health conditions.
Taking multiple medications, sometimes referred to as polypharmacy, can make it difficult to determine whether a new symptom is caused by an underlying illness, a newly developed condition, or a medication side effect. This can create a chain reaction in which one prescription leads to another, which is often missed in clinical practice.
“Prescribing cascades can be difficult to recognize because the original adverse effect may resemble a new medical condition,” study author Joyce Li, MSc, Research Manager at the Weston and O’Born Centre for Mature Women’s Health at Sinai Health in Toronto, explained to Medical News Today.
“Recognition is further complicated by variable timing with some prescribing cascades developing within weeks, whereas others may develop over several months. In addition, the large number of possible medication combinations, and the chronic use of many medications by older adults increases the risk for a potentially inappropriate prescribing cascade to occur and makes identification during routine care challenging.”
– Joyce Li, MSc
The researchers also note the potential relevance of prescribing cascades for mature women. Research suggests that females are
Taking several medications simultaneously may therefore increase the opportunity for a side effect to be interpreted as a new health problem.
The researchers emphasize that the issue is not simply the number of medications a person takes, but whether each medication has a clear indication and whether new symptoms are being appropriately evaluated in the context of a person’s existing treatment.
Kanwar Kelley, MD, JD, triple board certified in Otolaryngology Head & Neck Surgery (ENT), Obesity Medicine, and Lifestyle Medicine and Co-founder & CEO of Side Health in Orinda, CA, who was not involved in the study, highlighted common symptoms that may be dismissed and noted that limited communication likely contributes to PIPCs.
“A drug’s side effect resembles a brand-new medical condition. If a person begins taking a medication for high blood pressure, their ankles swell and this swelling is then treated with a diuretic rather than having the original drug reexamined,” Kelley told MNT.
“The situation is made worse by fragmentation in the U.S. healthcare system, patients see a number of doctors, none of whom have access to the full record and limited communication,” he noted.
“There are duplication and a chain of further treatments because none of the systems can share information,” said Kelley. “The typical symptoms that we dismiss as being due to aging are swelling, constipation, dizziness, nausea, and poor sleep.”
For the study, the research team included experts in internal medicine, geriatric medicine, and clinical pharmacology from Canada, the United States, Belgium, Italy, Israel, and Ireland.
The researchers had previously worked with 12 international experts to develop a list of 65 PIPCs. They then used population-level prescription data from ICES, Ontario’s health data institute, to investigate how frequently these medication sequences occurred.
For each potential cascade, the researchers considered 3 factors:
- how commonly the first medication was prescribed
- how often it was followed by the second medication
- how strong the association was between the two medications.
This analysis identified 24 PIPCs that were relatively common at the population level and had the potential to cause harm.
However, the findings do not necessarily mean that every person receiving medications in one of these sequences will experience a PIPC. Rather, the medication combinations can serve as signals that a person’s treatment may warrant closer review.
The connection between medications and subsequent symptoms is often missed in clinical settings and may not always be discussed during healthcare visits. A medication review therefore involves more than simply creating a list of the drugs a person currently takes.
Clinicians may also need to consider why each medication was started, when it was introduced, and what happened afterwards. A new symptom that appears after a medication is started may warrant a review of that medication before another prescription is added.
“Potentially inappropriate prescribing cascades are of particular concern for older adults, as they are more likely to have multiple chronic conditions, and therefore at greatest risk of polypharmacy (taking 5 or more medications) and medication-related harm,” Li emphasized to MNT.
“When unrecognized, they can increase treatment burden, reduce adherence, and in some cases heighten the risk of hospital admission.”
Kelley also noted that the potential for medication-related harm among older adults is significant and underappreciated:
“A study of 2.3 million older adults found two dozen cascades common enough to matter at the population level, with some affecting more than one in 10 patients who start the first drug. The harm grows worse since when you add a drug to treat a side effect, that drug in turn has its own side effects and leads to the next prescription. Even if only a fraction of these cases is real, the total amount of harm that can be avoided is considerable.”
The researchers suggest that technology could eventually help clinicians recognize these medication patterns at the point of care.
Automated clinical decision-support systems could potentially identify when a new prescription follows a medication known to cause a particular side effect. The system could then prompt the clinician to consider whether the new symptom might be related to the existing medication.
Such tools could flag a prescribing cascade in real time and prompt a second look before adding a new prescription to an already complex treatment regimen.
“Clinical decision-support tools and integration into electronic health records presents important opportunities. Our findings provide the foundation for the development of tools that could alert prescribers and pharmacists to potentially inappropriate prescribing cascades when a new medication is added or an existing medication is reviewed,” Li highlighted.
Similarly, Kelley highlights that technology could play a key role if implemented correctly: “The study’s real value is that it ranked cascades by how often they actually happen — which is everything, because the failure mode of these tools is alert fatigue.”
“Flag all 65 and clinicians tune it out; flag the two dozen that matter, when a second drug is added, and they’ll read it. A system that reads the sequence and asks, “is this new drug treating a side effect of the last one?” is doing real work. But these are signals, not verdicts — and the technology is the easy part. The harder question is whether anyone has 15 minutes to act on the flag,” he noted.
More closely integrating pharmacists could also be an important part of the solution.
Involving them in the prescribing and medication-review process could provide another opportunity to identify PIPCs. Pharmacists’ expertise in medication effects and interactions may help healthcare teams determine whether a new drug is addressing a genuine new condition or a side effect of an existing treatment.
People taking multiple medications may find it useful to keep an up-to-date list of their prescriptions, including medications that were recently started or stopped.
They can also ask their healthcare professional:
- Why was this medication prescribed?
- Could any of my medications be causing this new symptom?
- When did this symptom begin compared with when I started the medication?
- Do I still need all of my current medications?
- Could there be an alternative to adding another medication?
Importantly, it is not advisable for people to stop prescription medications without first discussing it with a healthcare professional.
“Patients can play an important role by advocating for themselves and asking questions about their medications: ‘Is every medication I’m taking still necessary?’ or ‘Could this new symptom be a side effect of something I’m already taking?’,” Li noted.
“It is also important that patients and/or their caregivers keep an up-to-date list of all their medications, including when they were started, why they were prescribed, and who prescribed them. This is particularly important because medications may have been started years ago, and the clinician reviewing them may not know the full history. This information can help to identify the sequence of events that may lead to a prescribing cascade.”
– Joyce Li, MSc
“If the patient sees multiple healthcare providers, encourage them to advocate for themselves and request that their medications be reviewed regularly and that everyone involved in their care has an up-to-date medication list,” she advised.
The Ontario study highlights a broader challenge in medication safety: sometimes the most important question is not whether a new symptom can be treated with another drug, but whether an existing medication may have caused the symptom in the first place.
Recognizing that possibility could help reduce unnecessary prescribing and limit medication-related harm, particularly among older adults taking multiple medications.
Team Health Accessible
Health & Wellness Editorial Team
HealthAccessible editorial team delivers trusted, accessible, and evidence-based health information for everyone.
