US Pharm. 2024;49(9):38-42.

OTC medications are essential in modern healthcare, offering accessible and affordable treatment options for common ailments without requiring a prescription. These medications, including analgesics, cold and flu remedies, antacids, and more, are widely used by consumers to manage minor health issues; 81% of adults turn to OTC medicines as their first response to minor ailments. This widespread usage underscores the significance of OTC drugs in the American healthcare landscape. These readily available products provide symptom relief to an estimated 60 million people who might otherwise forgo treatment. On average, households spend approximately $645 annually on OTC products—an 8% increase compared with 2021.1,2

The use of OTC medications for colds and allergies is particularly widespread, comprising a significant portion of the OTC drug market. In the United States, cold, allergy, and sinus OTC medication sales amounted to approximately $1.2 billion in 2023. The common cold—a prevalent condition—is typically an acute, self-limiting viral infection of the upper respiratory tract, most frequently caused by rhinoviruses. Common symptoms include coughing, nasal congestion, low-grade fever, and fatigue, usually appearing 1 to 2 days after exposure and generally subsiding within 7 to 10 days; however, some symptoms can persist for up to 3 weeks. Allergic rhinitis (AR) is another highly prevalent condition characterized by clear rhinorrhea, nasal congestion, sneezing, postnasal drip, and itching of the eyes, ears, nose, and throat. Current data suggest that up to 30% of adults and 40% of children suffer from AR, making it a common primary diagnosis for outpatient visits.2-4

Many products are available to relieve the symptoms of the common cold and AR. However, before recommending an OTC treatment, it is crucial to assess whether the patient is a suitable candidate for self-care (see TABLE 1). Therapies available for symptom relief from cold-like symptoms include antihistamines, decongestants, expectorants, antitussives, and analgesics/antipyretics, either as monotherapy or in combination. For AR symptom relief, common OTC options include intranasal corticosteroids, antihistamines, and decongestants. It is important to note that OTC medications can be dangerous for children aged younger than 2 years; in 2008, the FDA recommended avoiding OTC cough and cold medications for this age group. Since then, manufacturers have updated product labels to state “Do not use in children under 4 years of age.” For children aged 4 to 6 years, there is limited evidence of significant clinical benefit from OTC products for common-cold treatment.5-7

Given the prevalence of these conditions and the availability of numerous OTC products, careful consideration is essential when selecting appropriate self-care options. Pharmacists play a crucial role in guiding patients to appropriate OTC choices for cold and allergy symptoms, helping to ensure safe and effective use.

Decongestants

For patients experiencing nasal congestion, systemic or topical decongestants can be effective. Decongestants, which are adrenergic agonists, cause vasoconstriction that decreases sinusoid vessel engorgement and mucosal edema. Common systemic decongestants in OTC medications include phenylephrine and pseudoephedrine. Topical decongestants feature short-acting agents like ephedrine, naphazoline, and phenylephrine, as well as the longer-acting oxymetazoline.

Oral pseudoephedrine tends to be more effective than phenylephrine. Studies have shown that pseudoephedrine significantly outperforms both phenylephrine and placebo, while phenylephrine’s effects are not significantly different from placebo. This could be due to phenylephrine’s extensive systemic metabolism, leading to low bioavailability. Despite its widespread use in OTC cold and allergy medications, the effectiveness of oral phenylephrine has been questioned. Recent studies and an FDA advisory committee have concluded that oral phenylephrine is not effective for nasal congestion relief. Nevertheless, phenylephrine remains widely available. Pseudoephedrine, while effective, is regulated and placed behind pharmacy counters due to its use in illegal methamphetamine production. New formulations of pseudoephedrine aim to deter this misuse without compromising its decongestant properties.8-12

Topical decongestants also provide effective relief for nasal congestion. These agents act locally on the nasal mucosa with limited systemic absorption, resulting in fewer side effects. For example, a single-dose trial of oxymetazoline reduced nasal airway resistance and alleviated nasal blockage within 1 hour, with effects lasting up to 7 hours. However, the use of topical decongestants should be limited to 3 to 5 days to avoid rebound congestion, also known as rhinitis medicamentosa.13,14

When used appropriately, decongestants are relatively safe, but they can cause various adverse effects due to their direct action on adrenergic receptors and central nervous system (CNS) stimulation. Common side effects include insomnia, increased blood pressure, restlessness, anxiety, tachycardia, palpitations, arrhythmias, hallucinations, and urinary dysfunction. Decongestants should be avoided in patients with heart disease, hypertension, thyroid disease, diabetes, and benign prostatic hypertrophy. Additionally, they should not be used concurrently with monoamine oxidase inhibitors, as this combination can cause a life-threatening rise in blood pressure.15

Antihistamines

Antihistamines can help alleviate symptoms such as a runny nose, itchy and watery eyes, and sneezing by blocking the binding of histamine to the H1 receptor and preventing the release of histamine from mast cells. Antihistamines are categorized into first- and second-generation agents. First-generation antihistamines (e.g., diphenhydramine and chlorpheniramine) are highly lipophilic and easily cross the blood-brain barrier, leading to adverse CNS effects, including sedation, drowsiness, and decreased cognitive processing. Due to their anticholinergic profile, they should be avoided in the elderly population. In young children, diphenhydramine has been associated with paradoxical excitation, causing irritability, hyperactivity, and insomnia.16,17

Second-generation antihistamines are more lipophobic, resulting in poorer penetration of the blood-brain barrier and a lower likelihood of sedation compared with first-generation agents. These agents have longer half-lives, allowing for once- or twice-daily dosing, unlike first-generation antihistamines, which require multiple daily doses due to their shorter half-lives. While second-generation agents are generally nonsedating, cetirizine and levocetirizine carry a modest risk of sedation. Although first-generation antihistamines effectively control symptoms such as a runny nose, itchy and watery eyes, and sneezing, second-generation antihistamines are preferred due to their improved safety and efficacy profile and better selectivity for the histamine receptor.18-20

Intranasal Corticosteroids

Intranasal corticosteroids are potent anti-inflammatory agents that relieve sneezing, rhinorrhea, nasal congestion, nasal itching, and ocular symptoms. It is important to educate patients about the onset of action of these agents; the onset of action after the first dose ranges from 3 to 36 hours but may take up to 1 week for patients to experience full relief.18,21

The efficacy and adverse event profiles of intranasal corticosteroids are similar across different formulations. When recommending a specific agent, consider factors such as product sensory attributes (aftertaste, nose runout, throat rundown, and smell), as well as each medication’s distinct physicochemical properties. Generally, intranasal corticosteroids are well tolerated, with the most common adverse effects resulting from local mucosal irritation, including dryness, burning, stinging, and epistaxis. In rare cases, nasal septal perforation can occur. Proper administration techniques are essential to optimize efficacy and minimize adverse effects. The topical administration of corticosteroids significantly reduces bioavailability, thereby minimizing the risk of systemic side effects.18,22

Antitussives

Many OTC cold preparations include dextromethorphan, an antitussive used to suppress the cough often associated with the common cold and other respiratory infections. While it is available as a single-agent preparation, dextromethorphan is more commonly found in combination with other ingredients in multisymptom cold and flu products. Numerous studies have evaluated the efficacy of these products, but small sample sizes, poor study design, or variability in dosing and frequency of use limit many. Although some reviews suggest that dextromethorphan may be effective in treating acute cough based on cough-counting studies, others conclude that there is no strong evidence for or against its use in managing cough. This variability in findings highlights the need for more rigorous and well-designed studies to determine its effectiveness conclusively.23,24

When consumed in excessive doses, dextromethorphan can produce hallucinogenic effects similar to those of phencyclidine and ketamine. This has led to the drug being abused by some individuals. Surveillance data indicate that the peak prevalence of dextromethorphan abuse occurred in 2006, with an estimated 17.6 cases per million. Potential physiological effects of high-dose dextromethorphan abuse include, but are not limited to, tachycardia, mental-status changes, hypertension, seizures, coma, and both respiratory and cardiac arrest. The abuse potential of dextromethorphan has resulted in numerous states enacting legislation prohibiting the sale of the drug to minors.25,26

Expectorants

Expectorants are agents that are generally employed to reduce the viscosity and volume of sputum produced in patients suffering from a variety of respiratory conditions. Guaifenesin is the only FDA-approved expectorant and is found in a variety of remedies for the symptomatic relief of acute, ineffective productive cough. Although guaifenesin s available in OTC preparations for decades, the efficacy of guaifenesin as an expectorant in cold and flu preparations continues to be questioned. A 2014 Cochrane review of cough and cold products failed to find any clinical evidence supporting the clinical efficacy of the drug either alone or in combination.23

Despite the lack of trials demonstrating clinical benefit, guaifenesin continues to be promoted as an effective expectorant in OTC products. The drug is considered relatively safe and is not associated with any clinically significant drug interactions. When used at recommended doses, the drug is relatively well tolerated, with the most common side effect reported being gastrointestinal intolerance.

Analgesics

OTC analgesics and antipyretics, such as aspirin, acetaminophen, ibuprofen, and naproxen, are often employed to manage the generalized pain, headache, and fever associated with the common cold and other viral illnesses. Although these agents are generally considered equally effective in managing the above symptoms, they should be used judiciously, as they are associated with several adverse effects.10 Patients with aspirin allergy and those with active ulcers may not be candidates to receive aspirin or related nonsteroidal anti-inflammatory drugs (NSAIDs). In addition, a recent study suggested that patients who use NSAIDs during an acute respiratory infection tripled their risk of acute myocardial infarction.27

Role of the Pharmacist

Many people take OTC medications for relief when faced with symptoms such as a runny nose, itchy eyes, or congestion. By offering expert advice and guidance, pharmacists can ensure these products’ safe and effective use. Pharmacists can assist patients in selecting the right products based on their specific needs and medical history. Pharmacists can also identify potential drug interactions and educate patients about common side effects. Significantly, pharmacists can help prevent the misuse of OTC medications by emphasizing the importance of following label directions and avoiding unnecessary use. By providing comprehensive medication information and guidance, pharmacists can empower patients to make informed decisions about their OTC medication use and contribute to improved health outcomes.

Conclusion

OTC medications for cough and allergy remain a cornerstone of community healthcare, offering patients accessible relief for common symptoms. As the most accessible healthcare professionals, pharmacists are uniquely positioned to bridge the gap between self-care and professional medical advice. By providing expert guidance on OTC cough and allergy medications, pharmacists can significantly contribute to public health, ensuring that patients receive optimal benefit from these readily available treatments while minimizing potential risks. The future of OTC cough and allergy medications will likely see continued innovation and possibly further switches from prescription to OTC status. Pharmacists must remain adaptable, committed to ongoing education, and dedicated to patient-centered care. By doing so, pharmacists can continue to enhance the value of OTC medications in managing cough and allergy symptoms, and improving patient outcomes and quality of life.

What Are OTC Medications?

OTC medications are drugs you can buy without a prescription. They are used to treat common ailments such as headaches, colds, and allergies. They include pain relievers such as acetaminophen and ibuprofen, cough and cold products such as pseudoephedrine and guaifenesin, and allergy medications such as loratadine and cetirizine.

Are OTC Medications Safe?

While OTC medicines are generally safe when used as directed, it is important to understand their proper use to avoid potential risks. Follow these tips to ensure safe use:
• Read and follow the label instructions carefully.
• Follow the dosage instructions carefully. Do not take more than the recommended dosage.
• Know what is in your medicine to avoid taking multiple products with the same ingredient.
• Be cautious with combination products. Be aware of potential side effects, and stop using the medicine if you experience any serious side effects.
• Store medicines in a cool, dry place, away from children and pets.
• Always ensure that medicines are not expired.

Are There Risks to Taking OTC Medications?

Be aware of drug interactions. The OTC medicine you take could interact with other medications, supplements, or drinks. Check with your doctor or pharmacist before using OTC medicines. Pay attention to any health conditions or other medications that may interact with the OTC medicine. For example, people with high blood pressure should not take certain decongestants. Consider any allergies you may have. Consult a healthcare provider before using any OTC medicine. Dosages for children differ from those for adults; use pediatric versions when available. The elderly should also be cautious due to potential increased sensitivity.

General Tips When Taking OTC Medications

Read the drug facts label carefully and check the active ingredients. Use the correct device to measure the medicine, such as a measuring cup or syringe. Keep a list of all your OTC medications, including vitamins and supplements. Share this list with your doctor and pharmacist. Do not combine prescription medicines and OTC medicines unless your doctor or pharmacist says it is okay to do so. If your symptoms worsen or do not improve within a few days, consult a healthcare provider.

Where Can I Find More Information?

FDA OTC Medicine Information: www.fda.gov/drugs/understanding-over-counter-medicines/educational-resources-understanding-over-counter-medicine
National Library of Medicine. Over-the-Counter Medicines: www.medlineplus.gov/overthecountermedicines.html

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