Centrally acting antitussives

Fixed dose combination of salbutamol or any other bronchodialator with centrally acting antitussive and/or antihistaminics. 

Fixed dose combination or centrally acting antitussive with antihistaminics having atropine like activity in expectorants. 

In Japan, 3,17-dimethylmorphinan phosphate (Dimemorfan) has been marketed as a centrally acting antitussive agent,(54) and the related (+)-3-ethyl-17-methyl analog is reported in the patent literature to have analgesic and antitussive properties/543 ... 

Novoseven eptacogalfa factor VII. noscapine [ban, inn] (narcotine i-a-narcotine) is an alkaloid from Corydalis cava (Corydalis tuberosa), Papaver somniferum and other Papaver spp. It is a by-product in extraction of morphine from opium, and one of the first alkaloids to be isolated. It can be used as a centrally acting ANTITUSSIVE, similar in pharmacology to codeine, novobiocin [ban, inn] (Albamycin ) is an antibiotic with ANTIBACTERIAL activity against Gram-positive bacteria. It is also a LEUKOTRIENE RECEPTOR ANTAGONIST. 

It was recently recognized that opioid receptor agonists have antitussive effects [31]. Morphine (Fig. 7) is a potent p opioid receptor agonist that exhibits marked antitussive effect, and it has been used for the treatment of severe coughs. Codeine (Fig. 7) is one of the most reliable centrally acting antitussive agents its antitussive... 

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

Name two drugs that act as centrally acting antitussive agents and are analogues of morphine. Discuss the synthesis of one such compound. 

Dextromethorphan Dextromethorphan is the dextro- isomer of codeine. It is included in cough medicine because of its centrally acting antitussive effects. Dextromethorphan actions are unaffected by narcotic antagonists. It causes little sedation or Gl disturbances. 

Dextromethorphan HBr is the ( + )-isomer of the 3-methoxy form of the synthetic opioid levorphanol. It lacks the analgesic, respiratory depressant, and abuse potential of p opioid agonists but retains the centrally acting antitussive action. Dextromethorphan is not an opioid and is not listed in the Controlled Substances Act. Its effectiveness as an antitussive is less than that of codeine. Dextromethorphan is available in a number of nonprescription cough formulations. 

Current antitussives are broadly divided according to their site of action as either central or peripheral, although many act to some extent at both locations. Centrally acting antitussives act within the central nervous system (CNS) to suppress central cough pathways and comprise the majority of currently used drugs. However, opioids, which are gold standard antitussive agents, suffer from numerous... 

Kamei J (2002) Delta-opioid receptor antagonists as a new concept for central acting antitussive drugs. Pulm Pharmacol Ther 15 235-240... 

Bolser DC (2006) Current and future centrally acting antitussives. Respir Physiol Neurobiol 152 349-355... 

Central Mechanisms III Neuronal Mechanisms of Action of Centrally Acting Antitussives Using Electrophysiological and Neurochemical Study Approaches... 

Mechanisms of Action of Nonnarcotic Centrally Acting Antitussives. 223... 

An important question at this point is whether blockade of GIRK channels by antitussives causes inhibition of coughing. Interestingly, all centrally acting antitussives studied inhibited /5-HT caused by 5-HTia receptor activation. IC50 values of various antitussives for the current caused by 0.1 pM 5-HT ranged from 1 to lOpM. 

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