The Common Cold: Acute Illness, Drug Interaction Potential

Everyone's had one and will have another: a common cold. It's the most common acute illness in the United States.¹Americans suffer from 1 billion colds every year. Children contract 6 to 8 colds annually, while adults average 2 to 4.2 It’s a benign, self-limiting condition, but it’s irritating enough to stimulate a robust demand for OTC products to treat symptoms. Americans spend an average $300 million and $4.2 billion on products to prevent and treat cold symptoms yearly, respectively.³

Health care professionals (HCPs) usually recommend OTC products as first-line treatments.⁴They must evaluate these agents’ safety for each patient before making suggestions.

Mind the Ingredients

Many cough and cold remedies are multi-ingredient products.⁵Such products reduce pill burden, but also increase the risk of drug duplication and toxicity. Consumers may accidentally exceed maximum recommended dosages, especially for acetaminophen (adult maximum dosage is 4 g/day). Retail clinicians are responsible for educating patients to check ingredient lists.⁶

HCPs must also be aware of potential drug—drug interactions to ensure that patients use these products safely.⁷Even though most cough and cold products are available without a prescription, they can have significant adverse effects (AEs) and drug interactions.⁵Practitioners need to warn patients of potential harms.

Nasal Decongestants

Given either topically or systemically, nasal decongestants clear a stuffy nose.⁵Table 18,9 lists their significant drug—drug interactions. Decongestants have additive effects if taken with other sympathomimetics, so use should be restricted or monitored.^8,9

First-Generation Antihistamines

Cold symptoms are not histamine mediated. Regardless, antihistamines—and only the first-generation antihistamines—are used for their anticholinergic side effects (not to block histamine release). They reduce cold-related sneezing and rhinorrhea.⁵Consult Table 28,9 for a list of drug interactions.

Analgesics

Acetaminophen and ibuprofen relieve headaches and body aches associated with colds, but they have a significant number of drug interactions (see Table 38,9 ).⁵Retail clinicians should also caution patients to avoid alcohol consumption because of the risk of liver toxicity with acetaminophen and gastrointestinal bleeds with ibuprofen.⁵

Cough: Antitussives and Expectorants

Antitussives (see Table 48,9) are used to suppress coughs.⁵Recommend these products for nonproductive coughs (ie, mucus is not produced). Expectorants loosen mucus, allowing patients to cough it out.

Complementary and Alternative Medicine (CAM)

Patients use some common CAM products for cough/cold including zinc, vitamin C, and echinacea.²These have some drug interactions (see Online Table 5). Retail clinicians should inform patients that rather than treating the common cold, these products can reduce its duration. Oral zinc is only effective if taken within 24 hours of symptom onset, and prophylactic vitamin C can reduce the duration and symptoms of colds by 8%.¹¹

Nonpharmacologic Measures

Health care professionals should always educate patients on nonpharmacologic methods. Rest, hydration, and humidified air are key for recovery.¹²Saline nasal spray for congestion and honey for cough may also help.¹¹

Conclusion

The multitude of products available for cough and cold treatment can be confusing for many consumers. Box after box, they line OTC shelves. Physician and pharmacist expertise can guide selections. Before making any recommendations, it’s important to ask what other agents—OTC, prescription, and herbal—patients are taking so that interactions may be avoided.⁷

Melissa Laracy is a 2017 PharmD candidate at the University of Connecticut School of Pharmacy.

References:

1. Sexton DJ, McClain MT. The common cold in adults: treatment and prevention. UpToDate website. uptodate.com/contents/the-common-cold-in-adults-treatment-and-prevention. Accessed July 22, 2016.

2. Simasek M, Blandino DA. Treatment of the common cold.Am Fam Physician.2007;75(4):515-520.

3. LSS Financial Counseling. The cold and flu season is here, and guess how much it will cost? October 31, 2013. LSS Financial Counseling website. blog.conqueryourdebt.org/2013/10/31/cold-flu-season-guess-much-will-cost/. Accessed July 22, 2016.

4. Smith SM, Schroeder K, Fahey T. Over-the-counter (OTC) medications for acute cough in children and adults in community settings.Cochrane Database Syst Rev.

2014 Nov 24;(11):CD001831.

5. Montauk SL, Rheinstein PH. Appropriate use of common OTC analgesics and cough and cold medications.Am Fam Physician.Monograph No. 1. 2002. www.fda.gov/ohrms/dockets/dailys/02/Aug02/082202/80022395.pdf. Accessed August 1, 2016.

6. FDA. Notice to industry: final guidance for over-the-counter products that contain acetaminophen. November 16, 2015. FDA website. www.fda.gov/Drugs/DrugSafety/ucm310469.htm. Accessed July 29, 2016.

7. FDA. Drug interactions: what you should know. September 25, 2013. FDA website. www.fda.gov/drugs/resourcesforyou/ucm163354.htm. Accessed July 22, 2016.

8. Lexicomp, Inc. (Lexi-Drugs, Interact). Lexi-Comp Mobile. Accessed July 29, 2016.

9. Micromedex Solutions. http://www.micromedexsolutions.com/home. Accessed July 29, 2016.

10. CDC. Clinical immunization safety assessment (CISA) project current studies. August 28, 2015. CDC website. cdc.gov/vaccinesafety/ensuringsafety/monitoring/cisa/studies.html. Accessed July 29, 2016.

11. Livingston C, Cozzens J, Hamilton A. FPIN’s clinical inquiries. Treatments for symptoms of the common cold.Am Fam Physician.2013;88(12). aafp.org/afp/2013/1215/od3.html. Accessed September 9, 2016.

12. Goldman RD; Canadian Paediatric Society, Drug Therapy and Hazardous Substances Committee. Treating cough and cold: guidance for caregivers of children and youth.Paediatr Child Health.2011;16(9):564-569.