It’s cold season again

OTCs Today

Mary Warner

The common cold, a viral infection of the upper respiratory tract, affects millions of Americans each year. While adults have an average of 2 to 3 colds per year, children have even more, with most colds occurring in the fall and winter months. Most people recover from a cold within about 7 to 10 days, though people
with weakened immune systems, asthma, or conditions that affect the lungs may take longer to recover and/or develop serious illness such as pneumonia.

Because colds usually don’t become serious or last for more than a week or so, the symptoms can be bothersome and affect daily life, leading to self-medication. According to the Consumer Healthcare Products Association, patients spent almost $10 million on OTC cold and cough products in 2021.

Cold or flu?

Cold symptoms include sore throat, runny nose, coughing, sneezing, headaches, and body aches, while the flu frequently also causes fever and chills. Because the symptoms are so similar, it can be difficult to tell the difference between the two. Cold symptoms are usually milder than flu symptoms, and people with colds are more likely to have a stuffy or runny nose.

Colds generally do not result in serious health problems.

Treating a cold

There is no cure for the common cold, but patients have many choices in how to treat their cold symptoms, including decongestants, antihistamines, analgesics, and throat lozenges. Combination products containing more than one type of medication are common.

Decongestants relieve pressure on the sinus and decrease congestion by inducing vasoconstriction of the blood vessels in the nose, throat, and paranasal sinuses, which results in reduced swelling and mucus formation in these areas.

Decongestants are available as tablets, capsules, or as nasal sprays and eye drops. They can also be categorized as direct-acting, indirect-acting, and mixed-action. Phenylephrine, oxymetazoline, and tetrahydrozoline are direct-acting decongestants that bind directly to adrenergic receptors. Indirect-acting decongestants such as ephedrine stimulate the adrenergic receptor system by increasing the activity of norepinephrine at the postsynaptic α and β receptors. Mixed-action decongestants (e.g., pseudoephedrine) have both direct and indirect activity.

Because ephedrine and pseudoephedrine are chemically similar to methamphetamine, they can be used to create methamphetamine by chemical reduction, making them highly sought-after chemical precursors in the illicit manufacture of the drug. As a result, in 2006 Congress passed legislation requiring limited access of these products (i.e., they must be stored behind the counter in pharmacies), retrievable records of all purchases of the products, verification of the identity of all purchasers, and a limit that can be sold to a single purchaser (3.6 g daily and 9 g monthly).

Common adverse effects of decongestants include sleeplessness, anxiety, dizziness, excitability, and nervousness. Because these medications can also contribute to hypertension, patients at risk for hypertension should avoid decongestant use as much as possible.

Antihistamines reduce or block symptom-causing histamines and have historically been available as tablets, capsules, and liquids. In mid-2021, FDA approved the first OTC antihistamine nasal spray, azelastine (Astepro). Antihistamines have little effect on nasal congestion but can be effective for controlling a runny nose and sneezing.

Antihistamines are characterized as either first-generation (sedating) or second-generation (nonsedating). First-generation antihistamines were first approved by FDA in the 1930s, while second-generation antihistamines were first approved in the 1980s.

Both types affect histamine receptors in the brain and spinal cord, but while first-generation antihistamines cross the blood–brain barrier, which results in drowsiness, second-generation antihistamines don’t cross this barrier and therefore do not cause drowsiness at standard dosages.

Common first-generation antihistamines include chlorpheniramine, clemastine, diphenhydramine, and doxylamine. Adverse effects of first-generation antihistamines include CNS depression (e.g., sedation, impaired performance) and anticholinergic effects (e.g., dry eyes, mouth, nose, and/or vagina; blurred vision; urinary hesitancy and retention; constipation; and reflex tachycardia). Because first-generation antihistamines are listed as potentially inappropriate medications for older adults in the 2019 AGS Beers Criteria, these medications are not recommended for older adults.

Second-generation antihistamines include loratadine, cetirizine, and fexofenadine. The adverse effects seen in first-generation antihistamines are rarely found with these medications. Cetirizine has been shown to be more potent than loratadine or fexofenadine, but it can cause sedation in some patients.

Combination products often contain a decongestant and antihistamine along with an analgesic such as acetaminophen, ibuprofen, or aspirin, and a cough suppressant such as dextromethorphan. It’s important to understand what each product contains to avoid taking a double dose of one of the ingredients.

Throat lozenges can soothe a sore throat that accompanies a cold. These generally contain menthol with or without benzocaine.

What to tell your patients

Ensure that patients know that the common cold is caused by a virus and that antibiotics won’t make their symptoms resolve any sooner than they would without them. Advise them to see their doctor if symptoms worsen or fail to improve, or if they have a fever greater than 101.3 °F
lasting more than 3 days, a fever after a fever-free period, shortness of breath, wheezing, a severe sore throat, or sinus pain. To avoid spreading the cold to their family or others, patients should be reminded to wash their hands often, clean and disinfect high-touch surfaces, cover their cough, and not share drinking glasses or utensils with others. Finally, advise your patients to rest and eat well.

Further information can be found in APhA’s Handbook of Nonprescription Drugs and on the FDA and CDC websites. ■