Cold medicines are medications used by people with the common cold, cough, or related conditions. There is, however, no good evidence that cough medications reduce coughing. While they have been used by 10% of American children in any given week, they are not recommended in Canada or the United States in children six years or younger because of lack of evidence showing effect and concerns of harm. One version with codeine, guaifenesin, and pseudoephedrine was the 213th most commonly prescribed medication in 2017, in the United States, with more than two million prescriptions.
Types
There are a number of different cough and cold medications, which may be used for various coughing symptoms. The commercially available products may include various combinations of any one or more of the following types of substances:
Expectorants are substances claimed to make coughing easier while enhancing the production of mucus and phlegm. Two examples are acetylcysteine and guaifenesin.
Also employed are various substances supposed to soften the coughing, like honey or supplement syrup.
Effectiveness
The efficacy of cough medication is questionable, particularly in children. A 2014 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 emphasizes 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. They are not recommended in those who have COPD, chronic bronchitis, or the common cold. There is not enough evidence to make recommendations for those who have a cough in cancer.
Codeine was once viewed as the "gold standard" in cough suppressants, but this position is now questioned. Some placebo-controlled trials have found that it is ineffective against some forms of cough, including acute cough in children. It is thus not recommended for children. Additionally, there is no evidence that hydrocodone is useful in children. Similarly, a 2012 Dutch guideline does not recommend its use to treat acute cough.
A number of other commercially available cough treatments have not been shown to be effective in viral upper respiratory infections. These include for adults: antihistamines, antihistamine-decongestant combinations, benzonatate, anti asthmatic-expectorant-mucolytic combinations, expectorant-bronchodilator combinations, leukotriene inhibitors, ambroxol, and guaifenesin, sometimes with analgesics, antipyretics, anti inflammatories, and anticholinergics; and for children: antihistamines, decongestants for clearing the nose, or combinations of these and leukotriene inhibitors for allergy and asthma. However, antihistamines cannot be used as an empirical therapy in case of chronic, or non-specific cough, especially in very young children. Long term diphenhydramine use is associated with negative outcomes in older people.
Alternative medicine
may be a minimally effective cough treatment. A Cochrane review found the evidence to recommend for or against its use in children to be weak. In light of this they found it was better than no treatment, placebo, and diphenhydramine but not better than dextromethorphan for relieving cough symptoms. Honey's use as a cough treatment has been linked on several occasions to infantile botulism and accordingly should not be used in children less than one year old. Many alternative treatments are used to treat the common cold. A 2007 review states that, "alternative therapies 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 2014 review also found insufficient evidence for Echinacea. 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." Zinc gel in the nose may lead to long-term or permanent loss of smell. The FDA therefore discourages its use.
Adverse effects
A number of accidental overdoses and well-documented adverse effects suggested caution in children. The FDA in 2015 warned that the use of codeine-containing cough medication in children may cause breathing problems. Cold syrup overdose has been linked to visual and auditory hallucinations as well as rapid involuntary jaw, tongue, and eye movements in children. Cough medicines can be abused as recreational drugs.
History
was originally marketed as a cough suppressant in 1898. It was, at the time, believed to be a non-addictive alternative to other opiate-containing cough syrups. This was quickly realized not to be true as heroin readily breaks down into morphine in the body. Morphine was already known to be addictive.
Society and culture
Brands
Some brand names include: Benilyn, Sudafed, Robitussin and Vicks among others. Most contain a number of active ingredients. Sudafed is a brand manufactured by McNeil Laboratories. The original formulation contains the active ingredient pseudoephedrine, but formulations without pseudoephedrine are also being sold under the brand. In 2016, it was one of the biggest selling branded over-the-counter medications sold in Great Britain, with sales of £34.4 million. The effectiveness of phenylephrine by mouth as a nasal decongestant is questionable. Gee's Linctus is a cough medicine which contains opium tincture. New Zealand in 2019 moved it to prescription only. Coricidin, Coricidin D, or Coricidin HBP, is the brand name of a combination of dextromethorphan and chlorpheniramine maleate. Varieties may also contain acetaminophen and guaifenesin. Codral is a brand name manufactured by Johnson & Johnson and sold primarily in Australia and New Zealand. Codral is the highest-selling cold and flu medication in Australia.
Economics
In the United States, several billion dollars are spent on over-the-counter products per year.
Poisoning
According to The New York Times, at least eight mass poisonings have occurred as a result of counterfeit cough syrup in which medical-grade glycerin has been replaced with diethylene glycol, an inexpensive, yet toxic, glycerin substitute marketed for industrial use. In May 2007, 365 deaths were reported in Panama, which were associated with cough syrup containing diethylene glycol.
Abuse
A number of types of cough medicine are frequently abused. This includes those containing dextromethorphan and codeine. Abuse may result in hallucinations, loss of consciousness and death.
