Symptomatic Cough Suppressants

Cough suppressants have been traditionally divided into the central acting ones that include the opiates morphine, diamorphine, pholcodeine, and codeine, as being 

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This chapter will discuss the treatment approaches to acute and chronic cough, highlight the currently available disease-specific and symptomatic cough suppressants, and look into the development of more efficacious antitussives, particularly for chronic cough. The treatment of chronic cough has two aims specific treatments of causative factors (disease-specific), and symptomatic cough suppression. 

Table 1 Symptomatic cough suppressants for acute cough in adults...

Table 2 Studies of symptomatic cough suppressants in chronic bronchitis...

Table 4 Recommendations of the American College of Chest Physicians guidelines (2006) for symptomatic cough suppressants...

Although for many patients with chronic cough there may be adequate control with a careful diagnosis and specific treatments directed towards associated canse(s), for others, symptomatic cough suppressants may be needed. We need better treatments of the associated cause(s) and more efficacious symptomatic antitussives. 

Viral pneumonia is treated symptomatically with bronchodilators, antipyretics, analgesics, expectorants and mucolytics, and cough suppressants. 

Currently there are few effective cough suppressants and it has been concluded that patients requiring symptomatic relief in chronic cough derive a very low level of benefit from available drugs (Bolser 2006). Most effective are opioids such as codeine which produce a reduction in the frequency of cough of 19-60% (Bolser 2006 Morice et al. 2007). However, the usefulness of opioids is limited by their sedative properties and dependence liability (Bolser 2006). 

Cough suppressants containing dextromethorphan or codeine should be employed initially for symptomatic therapy of respiratory symptoms. Prolonged coughing unrelieved by codeine might benefit from a semisynthetic, centrally acting narcotic... 

Hydrocodone bitartrate/chlorpheniramine maleate is an anti-tussive combination. Hydrocodone suppresses cough reflex stimulates opiate receptors in the CNS and peripherally blocks pain impulse generation. Chlorpheniramine competitively antagonizes histamine at H,-receptor sites. They provide relief of cough and rhinorrhea and symptomatic relief of stubborn cough and runny nose caused by cold or allergy. 

Hydrocodone bitartrate/homatropine methylbromide is an antitussive combination. Hydrocodone suppresses the cough reflex stimulates opiate receptors iu the CNS and peripherally blocks pain impulse geueratiou. Atropine inhibits action of acetylcholine or other cholinergic stimuli at postgauglionic cholinergic receptors. They are used for symptomatic relief of cough. 

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