Cough medicine often contains cough suppressants or expectorants.
A cough medicine or cough and cold medicine, also known as linctus when in syrup form, is a medicinal drug used in those with coughing and related conditions. There is no good evidence for or against the use of over-the-counter cough medications in those with a cough. While they are used by 10% of American children weekly, they are not recommended in Canada and the United States in children 6 years or younger because of lack of evidence showing effect and concerns of harm.
There are a large number of different cough and cold medications. Some include: Benilyn, Sudafed, Robitussin and Vicks among others. Most contain a number of active ingredients. These may include combinations of: antihistamines, antitussives (cough suppressants), expectorants, decongestants and antipyretics.
The efficacy of cough medication is questionable, particularly in children. A 2012 Cochrane review concluded that "There is no good evidence for or against the effectiveness of OTC medicines in acute cough". Some cough medicines may be no more effective than placebos for acute coughs in adults, including coughs related to upper respiratory tract infections. The American College of Chest Physicians states that cough medicines are not designed to treat whooping cough, a cough that is caused by bacteria and can last for months. No over the counter cough medicines have been found to be effective in cases of pneumonia. There is not enough evidence to make recommendations for those who have a cough and cancer. They are not recommended in those who have COPD or chronic bronchitis.
Dextromethorphan (DXM) may be modestly effective in decreasing cough in adults with viral upper respiratory infections. However, in children it has not been found to be effective.
Codeine was once viewed as the gold standard in cough suppressants but this position is now questioned. Some recent placebo-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. Additionally there is no evidence that hydrocodone is useful in children.
A number of other commercially available cough treatments have not been shown to be effective in viral upper respiratory infections. These include in adults: antihistamines, antihistamine-decongestant combinations, benzonatate, and guaifenesin; and in children: antihistamines, decongestants for clearing up the nose, or combinations of these.
Honey may be a minimally effective cough treatment. A Cochrane review found the evidence to recommend for or against its use to be weak. In light of this they found it was better than no treatment and about the same as dextromethorphan for the amount of coughing. Honey's use as a cough treatment has been linked on several occasions to infantile botulism and as such should not be used in children less than one year old.
Many alternative treatments are used to treat the common cold. However, a 2007 review states that, "Complementary and alternative therapies (i.e., Echinacea, vitamin C, and zinc) are not recommended for treating common cold symptoms; however, ... 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 is mixed with respect to cough, and a 2011 Cochrane review concluded that zinc "administered within 24 hours of onset of symptoms reduces the duration and severity of the common cold in healthy people". 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.
While a number of plants and Chinese herbs have been purported to ease cold symptoms, including ginger, garlic, hyssop, mullein, and others, studies have either not been done or have been found inconclusive.
A number of accidental overdoses and well-documented adverse effects suggested caution in children.
Heroin was originally marketed as a cough suppressant in 1898. It was believed to be non-addictive.
Society and culture
In the United States several billion dollars were spent on over the counter products a year.
According to the New York Times, at least eight mass poisonings have occurred as a result of counterfeit cough syrup, substituting inexpensive diethylene glycol in place of glycerin. In May 2007, 365 deaths were reported in Panama, which were associated with cough syrup containing diethylene glycol.
^ abSmith, SM; Schroeder, K; Fahey, T (Aug 15, 2012). "Over-the-counter (OTC) medications for acute cough in children and adults in ambulatory settings.". The Cochrane database of systematic reviews8: CD001831. doi:10.1002/14651858.CD001831.pub4. PMID22895922.
^Chang CC, Cheng AC, Chang AB (2012). "Over-the-counter (OTC) medications to reduce cough as an adjunct to antibiotics for acute pneumonia in children and adults". Cochrane Database Syst Rev2: CD006088. doi:10.1002/14651858.CD006088.pub3. PMID22336815.
^Vestbo, Jørgen (2013). "Therapeutic Options". Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease. Global Initiative for Chronic Obstructive Lung Disease. pp. 19–30.