5

Medications for the Common Cold and the Flu

Anna, a forty-six-year-old woman, came to her neighborhood urgent care clinic complaining of cough, sneezing, runny nose, and sinus discomfort since the previous day. Upon signing in, she requested a prescription antibiotic, saying that she needed to get better quickly to attend an important business meeting later in the week. Medical evaluation suggested that she was experiencing the early stages of the common cold. The doctor told Anna she had contracted a viral upper respiratory infection, that she should get better within a week, and that antibiotics are not indicated for viral disorders. Anna expressed both surprise and dismay. She repeated her request for the antibiotic, saying that she knew her body and that she had always responded best in these circumstances when taking one. The physician again denied the request, adding that she should also avoid most over-the-counter (OTC) cold and cough medications because they offered little benefit and in some instances could be harmful. He recommended general supportive measures, especially plenty of rest. The patient said she understood, and they parted cordially.

Three days later the patient and doctor met again. This time Anna had a red rash all over her body except on her hands and feet, watery bowel movements, insomnia, and itching in her “private parts” associated with a white discharge. She reported that she had been very disappointed not to have received an antibiotic during her previous visit and had gone directly to another clinic where she had gotten a prescription for one. Along with that, she had also been taking two OTC cold remedies to help manage the runny nose and congestion. Her cold symptoms were now almost gone, which she attributed to the antibiotic, but the new problems were worse. She was experiencing well-known adverse effects associated with antibiotic therapy: allergic reaction, vaginal yeast infection, and diarrhea from disruption of gut flora. Her difficulty sleeping was likely due to the OTC cold products, both of which contained chemical stimulants. She was advised to stop the antibiotic and cold remedies immediately, prescribed appropriate antifungal therapy, and told to take a probiotic to help rebalance her microbiome. The doctor predicted she would be feeling better within a day or two, but cautioned that she should seek prompt medical attention if she developed shortness of breath, worsening diarrhea, fever, or abdominal pain. The latter symptoms could indicate infection with Clostridium difficile, a potentially dangerous condition often resulting from antibiotic therapy.

I hear stories like this all the time and believe that similar cases play out in doctors’ offices around the world. Colds are a nuisance, and we have been conditioned to believe that we have to take something to help us get over them. Colds are also the most common acute human illness. Most adults experience two to three of them annually; children fare worse, getting four to twelve colds each year. Generally considered benign, colds typically resolve within a few days without the need for specific treatment, although some symptoms may persist for up to two weeks. Nonetheless, colds are associated with an enormous economic burden, including more than $3 billion spent on OTC cough and cold remedies, more than $7 billion related to physician visits, and approximately $20 billion associated with lost work and school days.

The flu is also costly and is not at all benign. Many people with bad colds think they have the flu, but influenza is caused by a different virus, one that attacks the lower respiratory system and is associated with serious complications that can be fatal. According to World Health Organization estimates, between three and five million cases of flu-related illness occur annually, as well as 250,000 to 500,000 flu-related deaths. In the United States, the flu leads to more than 400,000 hospitalizations and thousands of deaths each year, most involving the elderly. These statistics do not include data from influenza epidemics, such as the 2009 H1N1 flu pandemic, which was noteworthy for causing severe illness and death even in previously healthy young people.

Hundreds of different viruses cause the common cold, with rhinoviruses the chief offenders, especially during the winter. Flu season runs from October through early May, peaking in January and February. Influenza viruses mutate frequently, foiling the immune system’s ability to recognize them and making it difficult to design effective vaccines. When people with colds or the flu cough or sneeze, they unwittingly release viral particles into the air that can be breathed in by others or can settle onto exposed surfaces. Viruses are able to survive on human skin and surfaces for hours and can be transmitted through touch. If the nose, mouth, or eyes are then touched, infection may occur. The best ways to reduce the risk of catching a cold or the flu are to avoid symptomatic people and wash your hands frequently and properly.

Symptoms of the common cold and the flu often overlap, but there are significant differences. Cold symptoms develop slowly, with a gradual onset of sore throat, sneezing, cough, nasal congestion, and drainage, sometimes accompanied by a general feeling of malaise. Flu has a short incubation period and is associated with rapid symptom development that may include fever, chills, fatigue, body aches, headache, cough, sore throat, and congestion. Symptoms of both the common cold and the flu mostly result from the immune system’s response to infection, as it releases compounds that stimulate inflammation, dilate blood vessels, and promote mucus secretion. (Most of the more than 20 million people who died in the 1918 influenza pandemic died from drowning as their lungs filled with fluid from an exaggerated immune response to the virus.)

THE FLU VACCINE

Strategies to prevent, and even to treat, both the common cold and the flu are similar, with two significant exceptions—getting the annual flu vaccine and using antiviral agents (discussed in the next section). Experts disagree about the value of flu shots. Scientists have to predict which viruses will cause influenza months before the actual flu season begins in order to produce a vaccine. Sometimes their results miss the mark. Effectiveness varies from year to year, topping out at 60 to 70 percent in a good year, when a strong match exists between the vaccine and the circulating viruses. Protection is less certain in the elderly, who may require higher doses. Vaccination is particularly important for people at high risk for flu-related complications, especially the elderly, infants and young children, those with chronic underlying heart and lung disease, and the obese.

When you get a flu shot, your body responds by producing antibodies to the strains of virus present in the vaccine. Most experts believe that vaccination provides some measure of protection. Studies suggest that it can reduce the risk of heart attack as well as flu-related pneumonia. On the other hand, reviews of data from healthy vaccinated individuals suggest a modest benefit at best and question the wisdom of widespread annual flu vaccination.

A variety of flu vaccines are available. If you opt to get a flu shot, ask for one that does not contain thimerosal, a mercury-based preservative that is being phased out. Mercury is a known neurotoxin. A list of vaccines and their thimerosal content is available from the US Food and Drug Administration (FDA).

THE PROBLEMS WITH COLD AND FLU MEDICINES

Overuse of Antibiotics

I must repeat that the common cold and the flu are caused by viruses. Antibiotics are active against bacteria, not viruses; thus, there is no role for antibiotic therapy in the treatment of uncomplicated colds or flu.

Nor do antibiotics have a role in preventing complications, such as sinusitis, that can develop as a result of a cold or the flu. Yet every year, tens of thousands of people with these illnesses demand prescription antibiotics from their doctors. In fact, a whopping 41 percent of all antibiotic prescriptions are directed against respiratory infections, most of them unnecessary or inappropriate. This is a big problem, as we’ve seen, both because antibiotics are responsible for the largest number of medication-related adverse reactions and because their misuse and overuse accelerate the development of bacterial resistance, a major threat to public health (see chapter 1). If you get a cold or the flu, do not ask your doctor for an antibiotic.

Antiviral Agents

No prescription medication yet exists that is effective for the prevention or treatment of the common cold, but prescription antiviral agents are available for flu treatment. Like the vaccine, they are of greatest benefit to those at risk for complications. Most healthy people who get the flu will be uncomfortable—sometimes very uncomfortable—for a few days but get better on their own, unless they have an unusually virulent strain of the virus, the kind that circulates during a worldwide influenza pandemic. Newer antivirals, termed neuraminidase inhibitors (NAIs), include zanamivir (Relenza) and oseltamivir (Tamiflu). These drugs impair the release of newly formed viral particles from infected cells. When first introduced, the NAIs were trumpeted as the treatment of choice for the flu. Experience suggests this was an overstatement. Studies show that NAIs shorten the duration of flu by about one day only. Alongside vaccination, they do appear to help prevent complications in those at risk, but they also have drawbacks. Zanamivir is associated with bronchospasm (wheezing) in individuals with chronic lung problems, while oseltamivir is known to cause dizziness, nausea, and vomiting. And just as bacteria have become resistant to antibiotics, the flu virus is beginning to develop resistance to NAIs, specifically to oseltamivir.

I would ask you to keep in mind that most people who contract the flu do not require medical attention or antiviral drugs, and they get better on their own.

OTC COLD AND FLU REMEDIES

It is estimated that 70 percent of cold and flu sufferers turn to OTC remedies. Most are ineffective, do not reduce the duration of illness, and are potentially dangerous, especially for children (see chapter 16). In 2008, the FDA issued a public health advisory stating that OTC cough and cold medications should not be given to infants and children under the age of two. Advisory action for all children under age eleven remains under consideration.

Many OTC cold and flu remedies contain acetaminophen (Tylenol) or nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) (see chapter 8). These products can help reduce fever and relieve body aches when dosed appropriately. But fever is a useful response to infection; at higher body temperatures the immune system’s defenses operate more efficiently. Unless fever is dangerously high (over 105°F/40.5°C), it may be wiser to make yourself comfortable with sponge baths and cool compresses than to lower fever with a drug.^* Acetaminophen and NSAIDs are at best marginally effective for other cold and flu symptoms and can cause serious adverse effects. Some data suggest that acetaminophen may actually suppress the immune response and worsen congestion in adults, and inadvertent acetaminophen overdose can lead to liver damage.

Antihistamines (see chapter 4) are mostly used for allergies, but people often take them for cold and flu symptoms—with minimal effect. Older antihistamines, such as diphenhydramine (Benadryl), can actually make things worse because they create thicker mucus that is harder to clear. These first-generation antihistamines are also sedating, making driving and the use of heavy machinery while taking them potentially dangerous. Newer second-generation antihistamines such as fexofenadine (Allegra), loratadine (Claritin), and cetirizine (Zyrtec) are supposed to be non-sedating, but they too can make you groggy or sleepy.

Cough medicines come in two forms—antitussives containing dextromethorphan, a compound related to opioids that temporarily suppresses the cough reflex, and expectorants—often with guaifenesin, long purported to thin mucus and make it easier to clear the airways but, in fact, minimally effective. Coughing is the body’s way of clearing mucus that may be compromising breathing passages. Dry coughs that are painful or debilitating, keep you up at night, or otherwise interfere with your daily activities can be effectively suppressed with dextromethorphan; productive coughs should not be suppressed. Sometimes coughing can continue for weeks after a severe respiratory infection; the term for this is post-viral tussive syndrome. If dextromethorphan fails to control the cough, a prescription opioid may be necessary.

Since congestion is a symptom common to both colds and the flu, oral decongestants are another popular class of OTC remedies. Congestion results from the dilation of blood vessels in the tissue lining the airway passages. Decongestants are chemically related to epinephrine (adrenalin), a stimulant. They activate receptors that shrink blood vessels down to normal size, thereby reducing swelling and congestion. There are problems with them, however. One agent, phenylpropanolamine, was removed from the market after it was found to increase risk of death in the elderly. Marketing of another decongestant compound, pseudoephedrine, has been restricted due to its illicit use to make methamphetamine. At present, most OTC oral decongestants contain a related stimulant, phenylephrine. Side effects include anxiety, dizziness, insomnia, palpitations, and, rarely, high blood pressure.

You can spray a topical decongestant, such as oxymetazoline (Afrin), directly into the nostrils. It provides more rapid relief than oral products do but should be used for only a short period of time, perhaps one to three days. With longer use, effectiveness wanes and you find yourself spraying it into your nose more frequently to manage rebound congestion (known as rhinitis medicamentosa). This represents the body’s homeostatic reaction to the drug: nasal congestion worsens and persists. Continual use of topical decongestants makes for a vicious cycle of drug dependence.

Since all decongestants are stimulants, caution is recommended for people with poorly controlled hypertension, irregular heart rhythms, heart disease, or glaucoma. These medications can also impair bladder muscle activity, leading to urinary retention. Those with known urinary dysfunction, as well as men with an enlarged prostate gland, should avoid them.

Many OTC cold and cough remedies combine pain relievers, cough suppressants, decongestants, and antihistamines. If you plan to use them, be sure to read the labels carefully—doubling up on certain compounds puts you at greater risk for toxic side effects. Some evidence suggests that these products may actually prolong illness by giving people the sense that they are treating the problem and can go about their business instead of resting to conserve energy.

INTEGRATIVE MEDICINE APPROACHES TO TREATING COLDS AND THE FLU

Herbal Remedies and Supplements

A variety of herbs and supplements can be used for the management of colds and the flu. Andrographis (Andrographis paniculata), an herb commonly used in traditional Indian medicine (Ayurveda), has been shown to reduce symptoms both alone and when combined with another herb, eleuthero (Eleutherococcus senticosus). Astragalus (Astragalus membranaceus), obtained from the root of a plant in the pea family, has been used for centuries in China to ward off respiratory infections. I recommend it preventively throughout cold and flu season, especially for people who tend to catch “everything going around.” I take it myself when I fly or am exposed to people who are coughing and sneezing. Astragalus is nontoxic and can be taken indefinitely. Echinacea (Echinacea angustifolia, purpurea, or pallida) can help the immune system fight infection, but results of studies examining its effects on the common cold have been mixed. Standardized extracts that contain both E. purpurea and E. angustifolia seem to be most effective, especially in adults. Elderberry (Sambucus nigra) has both anti-inflammatory and antiviral properties, and studies suggest it can significantly reduce the duration of flu symptoms; it is available in syrups and lozenges. In addition to its use in the kitchen, garlic (Allium sativum) is a powerful therapeutic herb with immune-stimulating properties as well as antiviral and antibacterial effects. I eat a small amount of raw garlic at the first sign of a cold, chopping a few cloves into my food. Products made from the African geranium (Pelargonium sidoides) may reduce the severity and duration of a cold. The homeopathic remedy Oscillococcinum, made from duck liver and heart, is promoted for treatment of the flu, but supportive evidence is weak. Probiotics may protect against fever, cough, and runny nose in children, but the data are less compelling for adults.

Most studies conclude that prophylactic vitamin C (200 to 500 milligrams daily, with larger doses supported in some studies) may help prevent the common cold, or at least reduce the severity and duration of symptoms. It seems most effective for those who are vitamin C deficient. Epidemiologic data suggest a correlation between vitamin D levels and the incidence of upper respiratory tract infections, including the flu. (Blood levels of vitamin D are lowest during winter months, when the incidence of colds and the flu is highest.) Research findings are mixed, but vitamin D supplementation may help prevent colds and flu in those with low levels. Zinc deficiency impairs immune system function, and studies using zinc sulfate, acetate, and gluconate against the common cold suggest a trend toward benefit if taken within the first twenty-four hours, although overall the evidence is weak. Adverse effects, such as nausea, are more common with lozenges than with syrups or tablets. Intranasal zinc may result in permanent damage to an individual’s sense of smell.

Lifestyle Modifications

Smokers are at increased risk for contracting respiratory tract infections and can reduce that risk by quitting. Chronic stress, lack of social support, and depression can all interfere with immune function, increasing risk of infection. Stress management practices and social engagement can be protective as well as enjoyable. Mindfulness meditation has been shown to reduce the incidence, severity, and duration of cold symptoms, as has moderate exercise. Excessive exercise, however, such as vigorous running, may temporarily increase the risk of infection. Adequate sleep is critically important in supporting optimal immune system function. If you get fewer than six hours of sleep a night, you are more likely to get a cold because the sleep-deprived body produces fewer of the natural killer cells it needs to destroy virus-infected cells. Aim for at least seven hours of sleep each night.

BOTTOM LINE

Colds and the flu are common, and their management requires common sense. Because they are viral illnesses, they should not be treated with antibiotics. Flu symptoms are worse than cold symptoms and in some instances may lead to complications, but most healthy people recover from both colds and flu on their own with no need for drugs, prescription or OTC. Prevention is the best strategy. Those most at risk for complications from the flu should get the annual flu vaccine and should also ask a doctor about the need for prophylactic antiviral therapy. Wash your hands frequently, get plenty of rest and sleep, limit exposure to people who are already sick, and eat foods rich in antioxidant vitamins and minerals, such as brightly colored fruits and vegetables and dark, leafy greens. Add immune-boosting mushrooms, such as maitake and shiitake, to your favorite recipes, including chicken soup, which has been shown to help reduce the severity of cold symptoms. Consider taking additional vitamin C and vitamin D during cold and flu season, and perhaps trying astragalus or andrographis as well. If you do get sick, cough and sneeze into your sleeve and do not go to work or school until you are feeling significantly better, to reduce the chance of infecting others. Use gentle saltwater gargles to help relieve a sore throat; consider taking elderberry, Oscillococcinum, echinacea, or a pelargonium remedy; and ask your doctor about a prescription antiviral drug if the flu hits you particularly hard. Limit the use of OTC remedies and avoid combining multiple cold and cough products to lessen the risk of adverse events. If symptoms worsen or persist beyond ten to fourteen days, contact your doctor.