Summary: Since colds are caused by viruses, antibiotics don't help. To relieve the symptoms of a cold, pain and fever medicines are beneficial. Decongestants, antihistamines and cough suppressants may be modestly helpful in older children and adults, but they result in no benefit in children under 5 years of age. Topical nasal decongestants (nose drops or sprays) may be more effective, but they can have more severe side effects. Vitamin C and possibly other vitamins might be helpful in treating or preventing colds.
Colds are caused by viruses infecting the respiratory system. Viruses and bacteria are both germs. Viruses are smaller than bacteria. Most bacteria can be grown in a petri plate while viruses cannot. The major difference between viruses and bacteria is that bacteria can be treated with antibiotics, while most viruses cannot be treated with antibiotics.
Since colds are due to viruses, antibiotics do not help. Why not take antibiotics anyway? Why take something that doesn't help? Many patients prefer taking antibiotics for a cold. Many doctors don't mind prescribing antibiotics for a cold. The only problem with this, is that antibiotics don't help. The subject of antibiotic use is discussed in greater detail in the next chapter.
Cold medications are not very helpful. There are four types of medications used to relieve cold symptoms: 1) pain/fever relievers, 2) decongestants, 3) antihistamines and 4) cough suppressants.
Pain and fever relievers such as acetaminophen (commonly known as Tylenol, Tempra, Panadol, APAP, paracetamol, etc.) and ibuprofen (commonly known as Motrin, Advil, Medipren, etc.) are highly effective at controlling fever and the minor aches and pains of a cold.
Decongestants taken by mouth such as pseudoephedrine and phenylpropanolamine are supposed to shrink the swelling of congested nasal membranes and passages. In theory, decongestants should alleviate nasal congestion and obstruction by opening the nasal passages. Unfortunately, decongestants don't work in young children. This is very clear from scientific studies. The most accurate type of scientific study is a randomized double blinded placebo controlled study. This means that patients are randomly assigned to receive a decongestant or a placebo (looks like medicine, tastes like medicine, but has no medicine in it). Patients and study investigators do not know which patients are receiving decongestant or placebo because the medication bottles only have code numbers written on them. Patients are instructed to take the medication assigned to them. Study investigators interview patients to measure the medication's benefits. Since no one knows whether they were taking medication or placebo, there is no pressure on anyone to falsify any results. When the study is completed, the medication bottle codes are revealed and only then do patients find out if they were giving their child real medicine or placebo. The beneficial effect of medication and placebo are compared using statistical tests.
In scientifically sound studies such as this, several studies have convincingly shown that decongestants taken by mouth do not work well in young children. Similarly cough suppressants do not work well in young children. Basically, decongestants and cough suppressants do not work at all for children under 5 years of age. In children above 12 years of age, decongestants and cough suppressants work similarly as they do in adults. In the in between group age 6 to 12 years of age, the benefit is modest at best.
How well do decongestants and cough suppressants work in adults? Recall the last time you took a cold medication for nasal congestion or coughing. Do you remember how well it worked? It sometimes works well, but it often does not work at all. This is the best that decongestants and cough suppressants can do. They work less well in children under 12 and they don't work at all in those under 5 years of age.
As a parent, you might feel the need to give your child decongestants or cough suppressants when your child has a cold. Why bother? These medications do not work in young children. Giving medication to small children is not easy. Why spend a lot of effort to give an unnecessary medication when there is no benefit? Concentrate on fever and pain medications which have a benefit and forget about cough and cold medications in young children.
The most popular cough suppressants available are DM (dextromethorophan) and codeine. Both are weak cough suppressants which act on the brain to suppress the cough reflex. During a cold, excess mucus is produced in the breathing passageways in the lungs. The body keeps the breathing tubes cleared of mucus by coughing, which rushes air through the breathing tubes bringing mucus upward allowing a person to swallow it or spit it out. Since the purpose of coughing is to keep the breathing tubes clear, why would we want to suppress it? If coughing were suppressed, mucus would collect in the lungs. Then this mucus would become infected and rotten, causing a serious pneumonia. Suppressing a cough is actually a bad idea.
But what if you need to get some sleep at night or you had to get through an important meeting without interruption from all that coughing; can cough suppressants be helpful? The body's cough reflex is very strong. If the body needs to cough because the airways need to be cleared of mucus, it will be very hard to suppress. Cough suppressants are weak and their effect is only modest. The doses specified on the medication label are too low to result in any significant cough suppression. It may be best to take double the recommended dose, but only use it once a day when you really need it. Discuss this dosing strategy with your physician. This suggestion does not apply to young children who do not benefit at all from cough suppressants.
Codeine is a prescription cough suppressant while DM syrups can be purchased without a prescription. Does this mean that codeine is better than DM? No, DM is just as effective as codeine. Codeine has more side effects such as drowsiness, nausea, itching and constipation. The side effects of DM are less than those of codeine. Codeine is a narcotic and is potentially addicting. Given that DM is just as effective as codeine with less side effects, DM should be preferred. That is, of course, if you plan to try a cough suppressant at all, since their cough suppressing effects are weak and it is actually a bad idea to suppress coughing completely.
Most coughs due to a cold are due to mucus production and throat irritation. Coughs due to irritated, scratchy throats are best treated with fluids. Syrups, cough drops, hard candy, saliva and water all do the same things to relieve throat irritation. Having a glass or bottle of water nearby is a very basic and effective means of relieving scratchy irritated throats. Some coughs are due to bronchospasm, which means that the tubes in the lungs become slightly smaller than they should be. Bronchodilators (medications which open the tubes in the lungs, enlarging them) will relieve bronchospasm. Asthma patients frequently have bronchospasm, but non-asthma patients also have bronchospasm sometimes. In these instances, bronchodilators will provide significant cough and congestion relief.
Antihistamines counteract some of the effects of histamine, which is a chemical released by our cells in response to an allergic reaction. Some allergic symptoms which develop during colds such as puffy/watery eyes, sneezing and some types of nasal drip, may improve with an antihistamine. Examples of antihistamines include diphenhydramine and chlorpheneramine. There are too many antihistamines on the market today to supply a list containing most of them. Antihistamines cause drowsiness and sometimes dry mouth and eyes. Some of the newer antihistamines do not cause drowsiness, but currently, all of these require a prescription.
Cold medications can be purchased individually, but many cold medications come in combination formulas. The most common combination is a decongestant with an antihistamine (examples include Contac and Dimetapp). A decongestant alone (for example, Sudafed) does not cause drowsiness. In fact, most decongestants are stimulants. Combination antihistamine/decongestants have drowsy and stimulant medications together, but most people become drowsy with these combination medications. However, many children become restless and agitated (drowsy and stimulated at the same time) with these medications and because of this, many children are noticeably fussy while on these medications. Fussiness is sometimes noted in children even with plain decongestants or plain antihistamines.
Decongestants applied directly into the nostrils (topically), as nose drops or sprays are usually more effective than decongestants given by mouth. Because the medication is applied directly, it is concentrated onto its target and it starts working very quickly. Decongestants taken by mouth must enter the stomach and slowly get absorbed into the bloodstream from the intestines. The decongestant medication then circulates through the body and some of it goes to the nose. Decongestant nose drops or sprays are fairly effective, but they have some unfortunate side-effects. When decongestant nose drops or sprays are used too long, the nose tissues become leaky and worse nasal congestion results. While this side effect usually takes several days, it may be safest to limit the use of these medications to two days at the most.
Most pediatricians do not recommend decongestants for small infants. Nasal suctioning using a suction bulb and a saline (dilute salt water) nose drops is the usual recommendation. Because no decongestants are involved, there are no side effects. About three saline drops are dropped into the nose, then the drops and nasal mucus are sucked out (aspirated) using the suction bulb. The opposite nostril should be pushed closed when suctioning. This method temporarily clears some of the nasal mucus congestion during an infant's cold. However, this method is only modestly effective. The mucus re-accumulates soon and repeated suctioning is required. Until a child can blow his/her nose into a tissue, bulb suctioning is the only routine way to clear the nasal passages.
If the nasal congestion is very severe and significant breathing difficulty results, your physician may then recommend nasal decongestant drops or a spray for relief. But these should be used temporarily and under the supervision of your physician, especially if your child is young.
There are many who believe that vitamin C can help to cure the common cold. It does not appear to be an instant remedy. Perhaps it shortens the duration of a cold. Perhaps taking it every day will prevent a cold. Unfortunately, there are no good scientific studies demonstrating that vitamin C helps in preventing or curing the common cold. Acknowledging this, vitamin C is has no significant harmful effects and it may have other benefits. Taking a vitamin C supplement every day may be beneficial, but it may be very difficult to scientifically demonstrate this benefit. Refer to the chapter on vitamins for a more detailed discussion of vitamin C. Eating citrus fruits or drinking a lot of orange juice provides vitamin C, but taking a single vitamin C pill provides much, much more. Children can take 250 mg or 500 mg chewable tablets once a day, while older children and adults can take 500 mg or 1000 mg tablets once a day.
References:
Smith MBH, et al. Over-The-Counter Cold Medications: A Critical Review of Clinical Trials Between 1950 and 1991. JAMA 1993;269(17):22.
Gadomski A, et al. The Need For Rational Therapeutics in the Use of Cough and Cold Medicine In Infants. Pediatrics 1992;89(4):774.
Hutton N, et al. Effectiveness of an Antihistamine-Decongestant Combination For Young Children With the Common Cold: A Randomized, Controlled Clinical Trial. J Pediatr 1991;118(1):125.