The Cold Facts

The season of colds, and sniffles and flu is in full swing. Each year, from September until March there’s a significant increase in the number of patients who call about fevers, cough, stuffy heads and congestion. So. let’s talk about colds this week–what causes them, and how to treat them prudently.

By the end of the first decade of the twentieth century, we had scientific proof that colds are infectious. But it wasn’t until 1956 (before you were born, right?) that the first common cold virus was isolated. Today, we know that six viruses are the chief culprits in ‘common cold’ syndromes. Rhinovirus tops the list, since it causes more than half of all colds. Respiratory syncytial virus (RSV) is a big actor and can also cause viral pneumonia. Coronavirus is another etiology. It was given this name because it has a halo appearance when viewed under the microscope. Parainfluenza virus, Adenovirus, and Influenza virus round out the list. Parainfluenza can cause the familiar ‘croup’ in children, and Adenovirus tends to cause more severe cold symptoms than rhinovirus. Interestingly, and surprising to most people, up to 20% of people infected with Influenza virus will have symptoms of a cold rather than the classic ‘flu’ symptoms.

Since colds and flu are two very common illness caused by viruses, antibiotics (which are only effective in treating bacterial infections) are useless in both treating symptoms and curing colds. In fact, people who take antibiotics for viral illnesses are risking allergic reactions, a host of side effects, and the development of resistant bacteria in their systems. What this means is that bacteria can alter their cell structures to become ‘immune’ to certain antibiotics when they are exposed to the antibiotics but not killed by them. It’s estimated by the CDC that up to 50% of the 100 million antibiotics prescribed yearly are unnecessary. So, don’t bug your physician into giving you an antibiotic for a cold. Rather than asking, “Why don’t you give me an antibiotic for this infection?”, your question should be, “Do I really need this antibiotic?” If your doctor answers, “I’m not sure. . .” you’re better off not taking one. Patient pressure to prescribe is cited as one of the chief factors in antibiotic over-prescribing. Ironically, many patients feel shortchanged if they don’t receive some kind of prescription for their ailments. So, please, don’t pressure your physician to cough up some drugs just because you’re ill. Remember, our bodies are remarkably resilient and efficient self-healers if given appropriate nutrition and fluids, enough rest, and moderate exercise.

So what does work to help treat colds? Over the counter antihistamines (such as Benadryl) have beneficial effects on the runny nose symptoms, but are often sedating. . .so use with caution. Interestingly, our newer nonsedating antihistamines don’t do much to alter cold symptoms though they have been a great boon to allergy-sufferers. Over the counter decongestants (both nasal sprays and oral forms) also help to open stuffy nasal passages, but I caution patients to use the nasal sprays no more than three to four days. Unfortunately, with prolonged use, these sprays can create a rebound congestion of nasal membranes. . .so the nose actually becomes ‘dependent’ on the spray to stay open. I personally use the sprays at bedtime for the worst three days of head and nose congestion. A good night’s sleep is priceless when recuperating from a bad cold. And, this is a good time to check your medicine cabinets for any pills containing the decongestant, phenylpropanolamine. The FDA is removing this medication from all drug products because it increases the risk of hemorrhagic stroke. But, have no fear, pseudoephedrine remains and is a very effective decongestant. Is this information getting too stuffy for you? Well, hang on, I’m almost through!

Over the counter NSAIDS (e.g. Ibuprofen) do help with the fever and aches of colds, but they can irritate stomachs with continued use. Of course, short term use of cough syrups is also beneficial. There are mixed reviews on the use of Zinc lozenges, Echinacea, and Vitamin C, but I am convinced that appropriate use of these agents is beneficial. And there’s ongoing research on three treatments that actually do combat the cold viruses themselves.

Tremacamra is a recombinant soluble intercellular adhesion molecule that inhibits rhinovirus replication by acting as a decoy. If you understand that sentence completely, you’re ready for your biochemistry diploma! However, it’s benefit is greatest when used after virus exposure but before cold symptoms develop.

Pleconaril is an agent that has activity against both enterovirus and rhinovirus. It binds to the virus and alters it just enough to keep it from being able to attach to cells. Additionally, it can also prevent the virus from replicating. Whether it will make it to market for general use remains uncertain. Studies have demonstrated mixed benefit to date.

Finally in this trio is AG7088. The drug seems to have broad antiviral activity and can be helpful even if added late in the virus life cycle. In preliminary studies, volunteers treated with AG7088 have lower viral concentrations and lower cumulative nasal mucus production than untreated cold sufferers. Of course, if this agent makes it to market, it will have a much sexier name than it does now!

So, in summary, if you’ve got a cold, rest, fluids, and over the counter medications will probably do you more good than any other treatments currently available. Do not pester your doctor for unnecessary antibiotics because they will not have any benefit in treating the typical cold. However, if your symptoms are no better or actually worsen within the normal 10 day period, you may have developed a secondary bacterial infection (such as sinusitis, bronchitis, or bacterial ear infection). In this instance, do alert your physician. Antibiotics would have a clear indication for these problems–and you won’t be bugging your doctor inappropriately for prescription drugs.

Stephen L. Hines, M.D.
January 2001