Cold remedies: Which ones provide relief

Tagged:  

No drug can kill any of the viruses known to cause the common cold, and symptomatic relief is the best you can hope for from over-the-counter (nonprescription) cold remedies. The question of which OTC drugs are effective has occupied researchers for two decades. Only a selected few can actually alleviate symptoms, and some have serious risks. The latest research shows no OTC cold medicines should be given to a young child.

There are plenty of nondrug approaches to alleviating symptoms. Many are just as effective as OTC medicines and a lot safer and less expensive. This issue of HealthFacts explores the ways to avoid a cold, the various home care measures that can be taken, and the OTC medicines that do and do not work.

No Need For MD
Annoying as the stuffy nose, watery eyes, coughing, and sneezing can be, a cold is no reason to seek medical attention. Too often, a doctor visit results in an inappropriate prescription for antibiotics. A cold is a viral infection, and antibiotics are effective only against bacterial infections. There is no evidence to support the common practice of taking antibiotics to prevent the development of a bacterial infection on top of a cold. In fact, the antibiotic is more likely to be effective if used only after the bacterial infection has developed.

How to Avoid a Cold
A cold is what doctors call a self-limiting condition--it will go away without treatment in seven to ten days. (Symptoms that last longer are probably due to allergy or sinusitis.) People tend to get fewer colds as they get older. More than 200 different viruses are known to cause the common cold, and a bout with each confers immunity.

Children get the most colds--from four to seven yearly-- because they are a "clean slate" without exposure to life's full range of viral possibilities. Young adults get three to five colds a year, and the number is higher for adults frequently exposed to young children. By the time a person is well into adulthood, the average yearly number of colds is two or three.

At least one study has borne out a prevailing suspicion that stress is a factor in developing a cold. A 1991 British study showed that high levels of psychological stress could nearly double the odds of catching a cold.

Contrary to popular perception, you don't catch a cold from drastic changes in temperature, sitting in a draft, going out in winter with wet hair or insufficient clothing, kissing a person with a cold, walking in the winter rain without boots, or drinking from the same cup as someone with a cold.

Some viruses are transmitted by direct inhalation of small particles that circulate around the room after sneezing, talking, or coughing. The majority, however, are passed by hand-to-hand contact with an infected person who has touched her eyes, mouth or the inside of the nose. The virus can live for hours on the fingers and days on a phone, desk, or other surface where it can be picked up by another person who touches his eyes, mouth, or inside of the nose.

This finding, which revolutionized medical thinking on cold transmission, comes from the ongoing research of Jack M. Gwaltney, Jr., M.D., and J. Owen Hendly, M.D., of the University of Virginia School of Medicine in Charlottesville. Hand-to-hand transmission applies particularly to the rhinoviruses, which multiply in the nose. This is a family of viruses responsible for most colds in adults.

The eye as a route of cold transmission took many by surprise, but the common habit of eye rubbing will, in effect, cause the virus to be deposited in the nose. From the eye, the virus travels down the tear duct between the eye and the nose.

To avoid passing on the virus, people with colds should wash their hands with soap and hot water frequently and thoroughly, particularly in the first three days of a cold when the person is most infectious. This advice, along with keeping hands away from the face, holds for people who live and work with someone who has a cold.

Colds are more common in the winter because people are indoors more often.

Home Care:
Preschool Kids
Several nonpharmacologic steps can be taken to make an infant or small child with a cold more comfortable. The nose can be cleared with a bulb syringe; salt water nose drops (teaspoon of salt and eight ounces of warm water) can be used instead of the OTC nasal decongestant drugs; warm humidified air can alleviate congestion; fluid intake should be increased; and the child can be put to sleep in right-angle position to facilitate nasal drainage.

The current issue of Healthy Kids, published by the American Academy of Pediatrics (AAP), cites a study of children given hot chicken soup and others given cold water. The hot liquid cleared the nasal passages faster than the cold liquid. (At least one study involving adults showed that hot chicken soup relieves nasal congestion symptoms better than other hot liquids.)

The AAP warns against giving vitamin C in large doses, that is, beyond the 60 milligram Recommended Daily Allowance, because it can cause an upset stomach.

Fever often accompanies a cold in small children, but it doesn't require treatment unless the child has a history of febrile (fever-induced) seizures. The AAP's Healthy Kids report identified as myth the common idea that a high fever indicates a more serious illness than a low fever.

"Parents tend to think that fever alone indicates the seriousness of an illness, but there really aren't correlations like that," according to Stephen Ludwig, M.D., chief of the Department of General Pediatrics at Children's Hospital in Philadelphia.

"A child can have a temperature of 104 degrees and be less ill than another child with 103 or 102 degrees. If your child has a moderate or even high fever but looks and acts well, that's O.K. If he has a lower fever but is unusually pale or is breathing rapidly, there could be a problem." Dr. Ludwig suggests that parents consult their pediatrician about what temperatures are considered normal, high, or low for your child's age.

Parents should not sponge a baby with cool water to bring down a fever because this will have a reverse effect. The chill will cause shivering which raises body temperature. Instead, the AAP recommends sponging a baby with tepid water.

Homeopathic remedies sold in health food stores, drug stores, and supermarkets are safe for young children (see page 1).

Home Care:
Adults and Adolescents
The advice about fluid intake (eight to ten glasses/daily), hot chicken soup, and bed rest applies to everyone with a cold. Most healthy adults, however, can tolerate high doses of vitamin C, which has been shown in clinical trials to reduce symptoms somewhat but did not prevent colds. The late Linus Pauling told HealthFacts in 1987 that these trials failed to give participants high enough doses.

At first sign of a cold, Dr. Pauling advised, adults can stop a cold by taking very high doses of vitamin C to their limit of tolerance, which can be anywhere from 18,000 to 60,000 mg. The point of tolerance is individual, he said, and you'll recognize your own limit once diarrhea occurs. The megadosing should stop once the cold is gone.

What about those warnings of 20 years ago about vitamin C-induced kidney stones? For her 1987 book entitled, The Right Dose: How to Take Vitamins and Minerals Safely, nutritionist Patricia Hausman found only eight such cases reported in the medical literature. Five occurred in people with a history of kidney stones which were reactivated by high doses (more than 4,000 mg/daily) of vitamin C. Hausman concluded that the general population can safely take 4,000 mg on a daily basis. But people who are predisposed to kidney stones, have serious kidney disease, or kidney failure should not take high doses of vitamin C.

In a letter to the editor of The Lancet (28 October 1988), Dr. Anne-Lise Gotzsche suggested putting vitamin C directly where it's needed: The way to take vitamin C when you have a cold is to stuff it up your nose. She related her personal experience of successfully reducing a "nasty cold" in one day to a "little trace of a cold." She put powdered vitamin C up to each nostril and sniffed hard. (Amount was unspecified.)

Whatever Happened To....
Ever on the lookout for the latest cold remedies, the media carried numerous reports over six years ago about the merits of a new steam machine. Blowing steam directly up the nose through a nozzle made some sense for the increased intranasal temperature could inhibit the replication of the rhinovirus. The idea spawned a variety of OTC gadgets dubbed "hair dryers for the nose," but two controlled clinical trials published early this year found this method did not inhibit viral replication or provide any lasting relief (JAMA, 13 April 1994).

Zinc is another cold remedy we don't hear much about any more. The main problem with zinc supplements is the vile taste. Unfortunately, efforts to disguise it with citrus and other flavorings interfered with efficacy. The obvious taste also confounds the standard clinical trial design in which participants are not supposed to know whether they are taking a placebo or the real thing.

Pure zinc gluconate can be purchased in tablet form at most health food stores. In a widely publicized 1984 study, people who took zinc gluconate shortened their colds to only 3.9 days, compared to 10.8 days for people taking a placebo. Effectiveness is dependent upon sucking a tablet containing 23 mg of zinc gluconate for at least ten minutes every two hours. Many who have tried this have decided they would rather have a cold.

OTC Cold Drugs:
Children
The major reason to avoid giving OTC drugs to young children is the complete lack of information on safety and efficacy. In a 1993 review for the Journal of the American Medical Association, Michael B. H. Smith, M.B., and William Feldman, M.D., assessed all clinical trials (106) involving OTC cold medicines published between 1950 and 1991 (JAMA, 5 May 1993).

Fewer than half of these studies met the criteria for a well-designed clinical trial, of these the reviewers found only two studies involving preschool children. Both showed no symptom relief. Worse, the review uncovered several studies showing that occasionally side effects, such as visual hallucinations and psychosis, can occur in young children.

Last month a national survey conducted by the Centers for Disease Control and Prevention raised questions about a common practice of giving acetaminophen (Tylenol) to preschool children (JAMA, 5 October 1994). The survey indicates that most mothers know that aspirin should not be given to children because it can lead to Reye's syndrome, a neurological disorder. But the unexpectedly high prevalence of acetaminophen use in young children is worrisome.

Michael D. Kogan, Ph.D., and colleagues at the U.S. Centers for Disease Control and Prevention conducted the survey of more than 8,000 mothers of three-year-olds. Most reported that a recent child illness had been treated with an OTC medication, most often Tylenol.

The investigators estimate that more than half of the children in the U.S. had been given at least one OTC medication during the previous 30 days. The high prevalence of use has occurred despite the dearth of scientific proof for the effectiveness of certain classes of OTC medications and the risk associated with improper use.

In an editorial that accompanied the survey, Ann Gadomski, M.D., called for rational use of OTC medications in young children. She warned that physicians should not be complacent about the frequent use of acetaminophen because "acute and chronic overdose can produce serious toxicity."

The correct dosage is 10 to 15 mg per kilogram of body weight every four hours as needed for pain and for fever reduction, wrote Dr. Gadomski. Yet she took a stronger stand when quoted in The Wall Street Journal soon after the new survey was published. "Without clinical trials, there's no way of knowing what dose is appropriate or effective in children."

Although acetaminophen and aspirin are clearly effective as analgesics (painkillers) and antipyretics (fever reducers), Dr. Gadomski calls into question any merit to the latter. "A recent study showed that temperature reduction alone does not produce the expected improvements in comfort, appetite, or fluid intake. The concomitant analgesic properties of OTC antipyretics may produce these improvements in behavior, comfort, and subsequently fluid intake, but these effects have not been documented."

Dr. Gadomski identifies two common misconceptions of parents regarding OTC use: acetaminophen cures or treats cold symptoms and that cough and cold medicines cure common colds. She cites another survey by a panel of six pediatricians which found the use of OTC cough and cold medicines to be the least "correct" out of all the OTC medications used in home.

Another parent misconception is the belief that OTC medicines relieve symptoms so the child is able to sleep. "In fact, many of these medications contain sedating ingredients, such as antihistamine and alcohol, that promote drowsiness and sleep but have little impact on symptoms otherwise," writes Dr. Gadomski.

Dr. Heinz Eichenwald, professor of pediatrics at the University of Texas and editor of the journal Pediatric Infectious Diseases, put it this way: "You certainly don't use antibiotics or analgesics like Tylenol in a kid simply because he has a cold," he said. "You give analgesics only if he seems to be suffering--not if you seem to be suffering."

OTC Cold Drugs:
For Adults and Adolescents Only
Most cold experts advise against the use of combination cold medicines because they take a "scatter shot" approach. Combination products are likely to include a drug for a symptom you may not have. Save money and unnecessary side effects by choosing a single-ingredient drug proven effective for your symptom and sold either generically or as a store brand.

This standard advice is strengthened further by the fact that antihistamine is usually in the most popular combination cold medicines, and for a long time, there has been much uncertainty about whether antihistamines work.

As expected, the 1993 review by Drs. Smith and Feldman did find some benefit to certain single-ingredient OTC medications. Unexpectedly, however, they also found the combination of antihistamine and decongestant "is useful in relieving a variety of cold symptoms." Their conclusion regarding combination medicine put the reviewers smack into the hornet's nest of professional disagreement.

The question of whether antihistamines work has divided cold experts since 1972, when the FDA began reviewing the efficacy all products sold over-the-counter. (Drug manufacturers were not required to prove effectiveness until 1962. By then, hundreds of thousands of OTC drugs were already on the market.) The few existing studies produced contradictory results.

Furthermore, all antihistamines may not be equal. The 1993 review by Drs. Smith and Feldman turned up three studies which found that the antihistamine chlorpheniramine reduced sneezing, nasal mucus, and general symptoms, but one study showed no efficacy. Chlorpheniramine maleate is the antihistamine used in the most topselling combination cold medicines like Contac and Dristan

The finding of any value to chlorpheniramine was challenged in a letter to the editor of JAMA (20 October 1993) in response to the work of Drs. Smith and Feldman. "We cannot agree with Smith and Feldman's statement that chlorpheniramine has been largely shown to reduce some of the annoying nasal symptoms accompanying the cold." The writers, Denise Luks and Matt Anderson, pharmacologist and physician respectively, state, "The literature on cold medicines is rife with methodological problems."

The Smith/Feldman review also located studies that looked at two other antihistamines, diphenhydramine and triprolidine hydrochloride, and found these drugs to be no better than a placebo in relieving symptoms of a cold. Thonzylamine, an older antihistamine, also showed no improvement in symptoms in two large trials.

To complicate things further, a yet-to-be published study by the country's leading cold expert, Jack Gwaltney, M.D., found a benefit to one antihistamine. At a conference on infectious diseases last month, Dr. Gwaltney presented a study of 184 people, which found that clemastine actually relieves some cold symptoms (New York Times, 9 October 1994).

The FDA, now into its 22nd year of reviewing all 300,000 OTC products, still hasn't come to a conclusion about antihistamines. "Antihistamines are tough because the [beneficial] effect is modest," said Michael Weintraub, M.D., director of the FDA's Office of OTC Drug Evaluations. In a telephone interview, Dr. Weintraub said the FDA is coming close to the end of its review, and the results will be announced at the advisory committee meeting later this month. The final ruling will be published in the Federal Register.

As for the relevance of Dr. Gwaltney's unpublished findings, Dr. Weintraub said the study was conducted with the best techniques, but it probably didn't have enough participants to demonstrate anything better than a modest effect. Clemastine isn't in any OTC cold medicines, though it is in the allergy medicines, Tavist-1 and Tavist-D. This did not seem to bother Dr. Weintraub who believes that all currently available OTC antihistamines are, in fact, equal. "Clemastine is similar to all the other antihistamines on the market," he said.

The "modest" benefit of antihistamines should be considered against the side effects of drowsiness, dry mouth, and constipation. Antihistamines' effects, both good and bad, are further heightened by alcohol intake. Drs. Smith and Feldmen found the most common side effects of combination cold medicines to be insomnia, nervousness, and irritability. Children are likely to experience hyperexcitability with both antihistamines and decongestants.

Decongestants
Oral decongestants, the other standard component of combination cold medicine, have generated an entirely different controversy: They worksomewhatbut are they worth it? The oral decongestants, pseudoephedrine and phenylpropanolamine, reduced nasal congestion, according to the Smith/Feldman review.

But Dr. Gwaltney is one who believes that oral decongestants should be avoided because they have systemic effects, working not only on the blood vessels of the nose but also on those of the rest of the body. The side effects of oral decongestants include increased blood pressure and pulse rate. As such, oral decongestants should be avoided especially by people with conditions like hypertension and diabetes which predispose them to heart disease.

Dr. Gwaltney also points out that oral decongestants produce too weak an effect, and nose drops or sprays should be used instead. Two drugs, phenylephrine and oxymetazoline, are effective nasal decongestants, according to Dr. Gwaltney. All are vasoconstrictors, which means they shrink the blood vessels in the nose. Ephedrine and xylometazoline are also safe and effective nasal decongestants, according to the FDA review.

Avoid a rebound effect (stuffy nose returns with a vengeance) by taking nose drops no more than three days. If the nose is still stuffy, use salt water nose drops. (Dissolve one teaspoon of salt in eight ounces of warm water.) Nasal solutions can become contaminated so rinse the applicator with hot water after use and don't share it with anyone.

Cough Medicine
No studies of cough medicines were designed well enough to provide accurate information on efficacy. One study involving guaifenesin, an expectorant, found that it thinned mucus in some people but didn't reduce cough frequency. This modest benefit would be realized only by someone with a productive cough.

As for people with a nonproductive cough, that is, a dry cough, the FDA has found only two drugs that are both safe and effective. They are dextromethorphan and codeine. Since codeine is a narcotic causing constipation and nausea as side effects, dextromethorphan should be tried first. Unfortunately, these drugs are difficult to find as single-ingredient drugs. Codeine is available only by prescription in some states, and in those where it can be purchased OTC, it is usually combined with other drugs.

It's a myth that suppressing a cough can cause pneumonia, according to Dr. Gwaltney. Though this could be true for people with a chronic obstructive pulmonary disease like emphysema, the potential for pneumonia, he says, does not apply to healthy people with a cold.

Sore Throat
The mild sore throat that comes with a cold can be relieved with moisture. Warm or hot liquids (tea and soup) and sucking hard candy can be effective, along with adding moisture to the room with a humidifier. When all else fails, try aspirin or acetaminophen.

A Final Word About Combination Drugs
People with small children have another reason to avoid combination cold medicines. Many are sold in brightly colored packaging, often without safety caps, attractive to children. The American Association of Poison Control Centers reports that OTC cold medicines are a frequent cause of unintentional ingestions in preschool kids. Serious effects are rare, but unintentionally swallowed cold medicines brings many a child to the emergency room for a stomach pumping.

Share this with your friends