Expectorants and Antitussives

Importantly, the narcotic analgesic agents (see Chapter 11) retained an almost comfortable status in this are upto the recent times, such as morphine, hydromorphone, codeine, hydrocodone, methadone and levorphanol. 

however, pertinent to mention here that in the reeent years, a good nttmber of newer drug substanees have been synthesized metieulously which remarkably exhibited significant antitussive characteristic feature absolutely devoid of the absurd and most diseouraging addiction liabilities of the aforesaid narcotic drugs. Surprisingly, quite a few of these agents usually exert their activity very mueh identical fashion via a central effeet. 

In early 1960s, two befitting hypotheses were put forward to expatiate most logically and convincingly the probable mechanism for the ultimate relief of cough, namely  

These hypothesis shall now be discussed briefly as under  

According to their considered proposal and suggested explanation — bronchodilation is a critically essential and important mechanism exclnsively responsible for the relief of cough . It 

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A. kankauensis fruits, roots as expectorant and antitussive, analgesic and antiasthmatic 15... 

Expectorants and antitussive agents may be broadly classified into the following three categories (/) Sedative Expectorants (n) Stimulant (Irritant) Expectorants iii) Centrally Acting Antitussive Agents. 

How would you classify the expectorants and antitussive agents Support your answer with the help of least one example from each category. 

Laminaria possesses remarkable properties that make it a wonderful component of dietary supplements. Due to its amazing medicinal benefits, it has been used in traditional Chinese medicine since centuries and is listed in the Chinese pharmacopeia. In general. Laminaria is considered as a cold, salty herb, prescribed to cleanse heat, resolve phlegm, and soften and disperse hard accumulations (e.g., goiters). It is often used to control edema, as an expectorant and antitussive, and as a remedy for testicular pain and swelling. Despite its salty character, the herb is slightly hypotensive. 

In Chinese medicine related Lobelia species (e.g., L. chinensis Lour, and L. sessilifolia Lamb.) are also used, the former primarily for jaundice and sores, wounds, ringworm, snakebite and insect bites, and malaria while the latter is used as an expectorant and antitussive and in treating bronchitis, ulcerous sores, snakebites, and insect and dog bites. Both herbs also contain lobeline and related alkaloids. 

G. biloba L. is a member of the Ginkgoaceae family, a gymnosperm that has survived unchanged from the Triassic period. In traditional Chinese medicine, the seeds (nuts) of G. biloba were used as an antitussive, expectorant, and antiasthmatic, and in bladder infection (20). In China, the leaves of G. biloba were also used for the treatment of asthma and cardiovascular disorders (21). Today, standardized concentrated extracts prepared from the leaves of G. biloba are used for the treatment of peripheral circulatory insufficiency, cerebrovascular disorders, geriatric complaints, and for Alzheimer dementia. For a more extensive treatment, readers are referred to the many authoritative reviews available, e.g.. Refs. (22-27). 

Expectorants Guaifenesin, 100-400 mg every 4 hours 600-1200 mg (extended release) every 12 hours Glytuss, Robitussin, various generic The only OTC expectorant recognized as safe and effective by the FDA. Often used with antihistamines, decongestants, and antitussives in combination products. 

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