(1197) The High Prevalence and Complexity of Over-the-counter Medication Misuse in Older Adults

Objectives: Older adults (people ≥65 years) are the largest consumers of over-the-counter (OTC) medications, as almost 50% use an OTC daily or weekly, and 25% use a combination of 10 or more OTC and prescription medications. Because OTCs are available without a prescription, there is little clinical consideration given to their unsafe use. However, OTCs pose a risk to patient safety. Adverse drug events (ADEs) associated with OTCs cause 178,000 hospitalizations each year. Older adults are exceptionally vulnerable to these risks due to age-related factors. Little is known about how older adults select and use OTC products, especially when symptoms persist after initial, short-term medication use. This is the first multi-site study designed to prospectively quantify the type and intended use of OTCs selected by older adults in community pharmacies where products are purchased.

Methods: Older adults (n=144) were recruited from 10 community pharmacies from a mid-Western health system. Participants were given hypothetical symptoms (either cough/cold/allergy, pain, or sleep symptoms) and asked to select one or more OTCs for self-treatment. After selection, they were asked to report how they would use the product at 1) the onset of symptoms and 2) if their symptoms persisted or worsened after initial treatment. They also reported the prescription and OTC medications they use at home and their health conditions. Participants’ OTC selections were evaluated for four types of misuse: 1) drug-age (identified from the 2019 Beers Criteria), 2) drug-drug (interactions with medications used at home), 3) drug-disease (contraindicated with health conditions), and 4) drug-label (use deviates the label’s indications or instructions).

Results: On average, participants were 73 years old, used 11 home medications, and had 5 health conditions. Of the 144 participants, 114 (79%) demonstrated at least one type of misuse when describing how they would use their OTC selections at the onset of symptoms. Overall, 363 instances of misuse were identified among these 114 participants (x̄=3.18 per participant), and 57 (50%) exhibited misuse in more than one category. There was a high prevalence of drug-drug and drug-label misuse, as 107 (94%) demonstrated misuse in one or both categories.

When these 144 participants described how they would use their selections if their symptoms persisted or worsened, 113 (78%) indicated that they would discontinue their OTC and call the doctor, use a non-pharmacologic treatment option, or continue using their selection in the same way. However, 31 (22%) indicated that they would change the use of their initial selection (increase dose, frequency, or duration) or add a new product. Of these 31 participants, 23 indicated a change that would contribute to further misuse. Overall, 110 instances of misuse were identified among these 23 participants (x̄=4.78 per participant), and 15 (65%) exhibited misuse in more than one category. Again, drug-drug and drug-label misuse showed the highest prevalence, as all 25 participants had misuse in one or both categories.

Conclusions: The results highlight the high prevalence and complexity of OTC misuse in older adults, with nearly 4/5 participants demonstrating misuse in one or more categories when treating symptoms at onset. Shedding light on this problem is crucial, as up until now, older adult OTC misuse has not been quantified and assumed to be non-existent. Knowing older adults’ OTC misuse prevalence is critical for understanding medication-associated risks, including how misuse contributes to ADEs and subsequent hospitalizations for this patient population. Next steps include increasing awareness of providers, older adult patients, and caregivers to the risks associated with OTC use and identifying interventions aimed at reducing older adult OTC misuse without limiting patient autonomy. As the point of sale for most OTC medications, community pharmacies are the natural leverage point for such interventions.