Cough medicine
Encyclopedia
Medication
A pharmaceutical drug, also referred to as medicine, medication or medicament, can be loosely defined as any chemical substance intended for use in the medical diagnosis, cure, treatment, or prevention of disease.- Classification :...
used in an attempt to treat cough
Cough
A cough is a sudden and often repetitively occurring reflex which helps to clear the large breathing passages from secretions, irritants, foreign particles and microbes...
ing and related conditions. For dry coughs, treatment with cough suppressants (antitussives) may be attempted to suppress the body's urge to cough. However, in productive coughs (coughs that produce phlegm
Phlegm
Phlegm is a liquid secreted by the mucous membranes of mammalians. Its definition is limited to the mucus produced by the respiratory system, excluding that from the nasal passages, and particularly that which is expelled by coughing . Phlegm is in essence a water-based gel consisting of...
), treatment is instead attempted with expectorants (typically guaifenesin
Guaifenesin
Guaifenesin INN or guaiphenesin , also glyceryl guaiacolate, is an expectorant drug sold over the counter and usually taken by mouth to assist the bringing up of phlegm from the airways in acute respiratory tract infections.-History:Similar medicines derived from the guaiac tree were in use as a...
, in most commercial medications) in an attempt to loosen mucus
Mucus
In vertebrates, mucus is a slippery secretion produced by, and covering, mucous membranes. Mucous fluid is typically produced from mucous cells found in mucous glands. Mucous cells secrete products that are rich in glycoproteins and water. Mucous fluid may also originate from mixed glands, which...
from the respiratory tract
Respiratory tract
In humans the respiratory tract is the part of the anatomy involved with the process of respiration.The respiratory tract is divided into 3 segments:*Upper respiratory tract: nose and nasal passages, paranasal sinuses, and throat or pharynx...
.
There however is no good evidence for or against the use of these medications in those with a cough. Even though they are used by 10% of American children weekly, they are not recommended in children 6 years of age or younger due to lack of evidence showing effect, and concerns of harm.
Pharmaceuticals
DextromethorphanDextromethorphan
Dextromethorphan
Dextromethorphan is an antitussive drug. It is one of the active ingredients in many over-the-counter cold and cough medicines, such as Robitussin, NyQuil, Dimetapp, Vicks, Coricidin, Delsym, and others, including generic labels. Dextromethorphan has also found other uses in medicine, ranging...
(DXM) may be modestly effective in decreasing cough in adults with viral upper respiratory infections. In children however it has not been found to be effective.
Codeine
Codeine
Codeine
Codeine or 3-methylmorphine is an opiate used for its analgesic, antitussive, and antidiarrheal properties...
was once viewed as the gold standard in cough suppressants. Some recent placebo
Placebo
A placebo is a simulated or otherwise medically ineffectual treatment for a disease or other medical condition intended to deceive the recipient...
-controlled trials have found however that it may be no better than placebo for some etiologies including acute cough in children. It is thus not recommended for children.
Ephedrine
Ephedrine
Ephedrine
Ephedrine is a sympathomimetic amine commonly used as a stimulant, appetite suppressant, concentration aid, decongestant, and to treat hypotension associated with anaesthesia....
is used in cough medicine, such as Mollipect
Mollipect
Mollipect is a trade name for a medication whose active substances are:*Bromhexine, a mucolytic agent. In addition, bromhexine has antioxidant properties.*Ephedrine, a sympathomimetic amine with stimulant and decongestant effect....
, in some countries.
Others
Other commercially available cough treatments have not been shown to be effective in viral upper respiratory infections, including in adults: antihistamines, antihistamine-decongestant combinations, Benzonatate
Benzonatate
Benzonatate or 2,5,8,11,14,17,20,23,26-nonaoxaoctacosan-28-yl para-butylaminobenzoate is a non-opioid oral antitussive with effects that last from 6 to 8 hours. Since it is not an opioid, benzonatate is not prone to abuse like some other cough medications such as codeine. Benzonatate was approved...
, and guaifenesin
Guaifenesin
Guaifenesin INN or guaiphenesin , also glyceryl guaiacolate, is an expectorant drug sold over the counter and usually taken by mouth to assist the bringing up of phlegm from the airways in acute respiratory tract infections.-History:Similar medicines derived from the guaiac tree were in use as a...
; and in children: antihistamines, decongestants or combinations of these.
Alternative medicine
HoneyHoney
Honey is a sweet food made by bees using nectar from flowers. The variety produced by honey bees is the one most commonly referred to and is the type of honey collected by beekeepers and consumed by humans...
may be a minimally effective cough treatment. However a Cochrane review found insufficient evidence to recommend for or against its use. The evidence is a single study of Buckwheat honey given before bedtime which provided better cough relief at night and improved sleep difficulty in children more than no treatment or dextromethorphan
Dextromethorphan
Dextromethorphan is an antitussive drug. It is one of the active ingredients in many over-the-counter cold and cough medicines, such as Robitussin, NyQuil, Dimetapp, Vicks, Coricidin, Delsym, and others, including generic labels. Dextromethorphan has also found other uses in medicine, ranging...
based over-the-counter cough medicine. However, honey's use as a cough treatment has been linked on several occasions to infantile botulism
Botulism
Botulism also known as botulinus intoxication is a rare but serious paralytic illness caused by botulinum toxin which is metabolic waste produced under anaerobic conditions by the bacterium Clostridium botulinum, and affecting a wide range of mammals, birds and fish...
and as such should not be used in children less than one year old.
Many alternative treatments are used to treat the common cold
Common cold
The common cold is a viral infectious disease of the upper respiratory system, caused primarily by rhinoviruses and coronaviruses. Common symptoms include a cough, sore throat, runny nose, and fever...
. However, a 2007 review states that, "Complementary and alternative therapies (i.e., Echinacea
Echinacea
Echinacea is a genus of herbaceous flowering plants in the daisy family, Asteraceae. The nine species it contains are commonly called purple coneflowers. They are endemic to eastern and central North America, where they are found growing in moist to dry prairies and open wooded areas. They have...
, vitamin C
Vitamin C
Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...
, and zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
) are not recommended for treating common cold symptoms... Vitamin C prophylaxis may modestly reduce the duration and severity of the common cold in the general population and may reduce the incidence of the illness in persons exposed to physical and environmental stresses."
A 2009 review found that the evidence supporting the effectiveness of zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
is mixed with respect to cough, and a 1999 Cochrane review found the evidence of benefit in the common cold inconclusive. However, a 2003 review concluded: "Clinical trial data support the value of zinc in reducing the duration and severity of symptoms of the common cold when administered within 24 hours of the onset of common cold symptoms." Nasally applied zinc gel may lead to long-term or permanent loss of smell. The FDA therefore discourages its use.
A review of sixteen trials of echinacea
Echinacea
Echinacea is a genus of herbaceous flowering plants in the daisy family, Asteraceae. The nine species it contains are commonly called purple coneflowers. They are endemic to eastern and central North America, where they are found growing in moist to dry prairies and open wooded areas. They have...
was done by the Cochrane Collaboration
Cochrane Collaboration
The Cochrane Collaboration is a group of over 28,000 volunteers in more than 100 countries who review the effects of health care interventions tested in biomedical randomized controlled trials. A few more recent reviews have also studied the results of non-randomized, observational studies...
in 2006 and found mixed results. All three trials that looked at prevention were negative. Comparisons of echinacea as treatment found a significant effect in nine trials, a trend in one, and no difference in six trials. The authors state in their conclusion: "Echinacea preparations tested in clinical trials differ greatly. There is some evidence that preparations based on the aerial parts of Echinacea purpurea might be effective for the early treatment of colds in adults but results are not fully consistent. Beneficial effects of other Echinacea preparations, and for preventative purposes might exist but have not been shown in independently replicated, rigorous randomized trials." A review in 2007 found an overall benefit from echinacea for the common cold however further analysis found problems with the interpretations of this review.
While a number of plants and Chinese herbs have been purported to ease cold symptoms, including ginger
Ginger
Ginger is the rhizome of the plant Zingiber officinale, consumed as a delicacy, medicine, or spice. It lends its name to its genus and family . Other notable members of this plant family are turmeric, cardamom, and galangal....
, garlic
Garlic
Allium sativum, commonly known as garlic, is a species in the onion genus, Allium. Its close relatives include the onion, shallot, leek, chive, and rakkyo. Dating back over 6,000 years, garlic is native to central Asia, and has long been a staple in the Mediterranean region, as well as a frequent...
, hyssop
Hyssop
Hyssop is a genus of about 10-12 species of herbaceous or semi-woody plants in the family Lamiaceae, native from the east Mediterranean to central Asia. They are aromatic, with erect branched stems up to 60 cm long covered with fine hairs at the tips. The leaves are narrow oblong, 2–5 cm...
, mullein
Mullein
The Mulleins are a genus of about 250 species of flowering plants in the figwort family . They are native to Europe and Asia, with the highest species diversity in the Mediterranean region.They are biennial or perennial plants, rarely annuals or subshrubs, growing to 0.5–3 m tall...
, and others, scientific studies have either not been done or have been found inconclusive.
Toxicity
According to the New York Times, at least eight mass poisonings have occurred as a result of counterfeit cough syrup, substituting inexpensive diethylene glycolDiethylene glycol
Diethylene glycol is an organic compound with the formula 2O. It is a colorless, practically odorless, poisonous, and hygroscopic liquid with a sweetish taste. It is miscible in water, alcohol, ether, acetone, and ethylene glycol. DEG is a widely used solvent...
in place of glycerin. In May 2007, 365 deaths were reported in Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...
, which were associated with cough syrup containing diethylene glycol.
Efficacy
The efficacy of cough medication is questionable, particularly in children. A 2008 Cochrane review concluded that "There is no good evidence for or against the effectiveness of OTC medicines in acute cough". In 2001, a meta-analysisMeta-analysis
In statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses. In its simplest form, this is normally by identification of a common measure of effect size, for which a weighted average might be the output of a meta-analyses. Here the...
indicated that some cough medicines may be no more effective than placebo
Placebo
A placebo is a simulated or otherwise medically ineffectual treatment for a disease or other medical condition intended to deceive the recipient...
s for acute coughs in adults, including coughs related to upper respiratory tract infections. In 2006, the American College of Chest Physicians
American College of Chest Physicians
The American College of Chest Physicians is a medical organization in the United States consisting of physicians and non-physician specialists in the field of chest medicine, which includes pulmonology, thoracic surgery, and critical care medicine....
published a guideline for whooping cough
Pertussis
Pertussis, also known as whooping cough , is a highly contagious bacterial disease caused by Bordetella pertussis. Symptoms are initially mild, and then develop into severe coughing fits, which produce the namesake high-pitched "whoop" sound in infected babies and children when they inhale air...
, a cough that is caused by bacteria and can last for months. The guideline pointed out that available cough medicines are not designed to treat whooping cough or its causative bacterium. Although the efficacy is inconclusive for children over 2 years of age, a number of factors including accidental overdoses and well-documented adverse effects suggested caution in the paedriatic prescription of cough syrups and medicines. No over the counter cough medicines have been found to be effective in cases of pneumonia.