How to Choose Over-the-Counter Medications Safely

Over-the-counter (OTC) medications are a cornerstone of self-care, yet their accessibility often masks significant safety risks when used incorrectly or without awareness of underlying health conditions. As of April 2026, emerging data from the World Health Organization’s Global Surveillance and Monitoring System for substandard and falsified medical products indicates that improper OTC apply contributes to approximately 200,000 preventable emergency department visits annually in high-income countries alone—a figure driven largely by drug interactions, inappropriate dosing in comorbid populations, and unrecognized contraindications in chronic disease management.

Key Clinical Takeaways:

• Common OTC analgesics like ibuprofen and acetaminophen carry narrow therapeutic indices in patients with renal impairment or chronic liver disease, necessitating individualized risk assessment.
• Decongestants containing pseudoephedrine or phenylephrine can exacerbate hypertension and interact dangerously with monoamine oxidase inhibitors (MAOIs) or certain antidepressants.
• Pharmacist-led medication reviews reduce adverse OTC drug events by up to 30% in polypharmacy populations, according to a 2025 Cochrane systematic review.

The Irish Times’ recent guidance on selecting OTC medications safely underscores a growing public health imperative: empowering consumers with evidence-based tools to navigate an increasingly complex marketplace of over 300,000 OTC products globally. While the article emphasizes label reading and avoiding duplication of active ingredients, it overlooks critical pharmacokinetic vulnerabilities in aging populations and those with multimorbidity—groups that represent over 65% of OTC users in Europe, per Eurostat 2024 data. A longitudinal study published in The BMJ (2024) followed 12,450 adults aged 65+ across Ireland and the UK, revealing that 41% experienced at least one adverse drug reaction (ADR) linked to OTC use over 18 months, with gastrointestinal bleeding and acute kidney injury as leading outcomes—risks amplified by concurrent use of prescription anticoagulants or ACE inhibitors.

Funded by the Health Research Board (Ireland) and the UK’s National Institute for Health and Care Research (NIHR), this research highlights a stark gap between consumer perception and physiological reality: many assume OTC drugs are inherently safe due to non-prescription status, yet their mechanisms of action—such as COX-1 inhibition by aspirin or ibuprofen—can disrupt mucosal integrity or platelet function in susceptible individuals. As Dr. Eleanor Byrne, lead pharmacologist at Trinity College Dublin’s School of Pharmacy, explained in a 2025 interview: “We’re seeing a silent epidemic of preventable harm not from illicit substances, but from well-intentioned self-medication. A patient taking low-dose aspirin for cardiac protection who then self-prescribes ibuprofen for arthritis may inadvertently abolish aspirin’s antiplatelet effect—this isn’t theoretical; it’s measurable in thromboelastography studies.”

“The real danger lies not in the drug itself, but in the assumption that accessibility equals safety. We need to reframe OTC use as a clinical decision, not a convenience choice.” — Dr. Eleanor Byrne, PhD, Trinity College Dublin

Similarly, Dr. Marcus O’Connell, a geriatrician at St. James’s Hospital in Dublin, warns about antihistamine misuse: “First-generation agents like diphenhydramine carry significant anticholinergic burden—linked to delirium, falls, and cognitive decline in older adults. Yet they remain widely available in sleep aids and cold formulations without adequate warning.” His 2023 cohort study in Age and Ageing (n=8,900) found that chronic diphenhydramine use increased dementia risk by 54% over five years, even after adjusting for comorbidities—a finding corroborated by the FDA’s 2024 Drug Safety Communication urging caution with anticholinergics in populations over 65.

These risks are not theoretical. In clinical practice, undiagnosed hypertension exacerbated by pseudoephedrine-containing decongestants remains a common precipitant of hypertensive urgency, particularly during winter months when respiratory infections peak. A 2024 analysis of Irish primary care records (HSE-ICGP dataset, n=210,000) showed a 22% spike in stage 2 hypertension presentations following OTC cold remedy purchases—a correlation strengthened by temporal prescribing patterns.

For individuals managing chronic conditions such as diabetes, CKD, or ischemic heart disease, the stakes are higher. The American Diabetes Association’s 2025 Standards of Care explicitly caution against NSAID use in patients with eGFR <60 mL/min/1.73m² due to accelerated renal decline—a threshold frequently overlooked in self-directed pain management. Likewise, those with a history of peptic ulcer disease face up to a 4-fold increased risk of GI bleeding when combining low-dose aspirin with OTC NSAIDs, per a meta-analysis in Gastroenterology (2023, n=15,600).

This is where professional oversight becomes indispensable. Community pharmacists, increasingly recognized as accessible clinical touchpoints, are uniquely positioned to mitigate these risks through structured medication reviews. In Ireland, the Pharmaceutical Society of Ireland’s 2023 “MedsCheck” initiative demonstrated that pharmacist-led consultations reduced inappropriate OTC selections by 37% in patients over 60—particularly when guided by tools like the STOPP/START criteria adapted for self-care scenarios. For patients navigating complex regimens, consulting a vetted community pharmacist for a personalized OTC safety assessment can prevent cascading adverse events.

Beyond the pharmacy, primary care providers play a critical role in proactive risk stratification. Patients with unexplained fatigue, edema, or labile blood pressure should be evaluated for occult OTC-induced organ stress—a consideration often missed in time-constrained visits. For those with refractory symptoms or diagnostic uncertainty, referral to a general internist with expertise in pharmacovigilance can uncover hidden contributors to morbidity, especially when integrating tools like the Medication Risk Screening Tool (MRS) or Beers Criteria into clinical workflows.

legal and regulatory literacy is essential for healthcare organizations distributing or recommending OTC products. Misleading marketing claims—such as “non-drowsy” formulations containing stimulants like caffeine or phenylpropanolamine—have triggered enforcement actions by the HPRA and MHRA. Entities navigating these complexities benefit from consulting healthcare compliance attorneys to ensure advertising aligns with FTC and EU Directive 2001/83/EC standards, thereby avoiding costly recalls or reputational damage.

The trajectory of OTC safety hinges on bridging the gap between consumer autonomy and clinical vigilance. Emerging innovations—such as AI-powered smartphone apps that scan product barcodes and cross-reference ingredients with personal health profiles (e.g., Medisafe’s 2025 OTC Safety Module)—offer promise, but only if validated against real-world outcomes. As regulatory agencies like the FDA and EMA explore risk-based reclassification of certain OTC agents (e.g., moving higher-dose NSAIDs behind pharmacy counters), the imperative remains clear: self-care must be informed, not assumed.

In an era where preventive medicine is paramount, the humble OTC shelf represents both opportunity and obligation. Empowering patients with knowledge is essential—but it must be paired with accessible, expert-guided safeguards to ensure that the pursuit of relief does not inadvertently precipitate harm.

*Disclaimer: The information provided in this article is for educational and scientific communication purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider regarding any medical condition, diagnosis, or treatment plan.*