Do anti-allergic drugs or anticholinergic drugs have a role in the treatment of asthma?

After the successful introduction of sodium cromoglycate (SCG) for the treatment of asthma, emphasis was placed on its apparent novel mechanism of action, the inhibition of inflammatory mediator release from mast cells. This opened the flood gates for numerous SCG-derivatives, many with oral efficacy and improved potency. The majority of these compounds were ineffective clinically, casting doubts on SCG's mechanism of action and questioning the importance of mast cells in asthma. However, information on the heterogeneity of mast cells has directed recent drug screening to new, more relevant models of asthma involving other inflammatory cells. Consequently, nedocromil sodium has emerged to perhaps lead a new generation of antiallergic drugs. Bronchodilator anticholinergic drugs have met with a resurgence of interest of late with the development of a number of quaternary ammonium homologues of atropine. While not as effective as beta-adrenoceptor agonists in asthma they are particularly effective in chronic obstructive pulmonary disease. Drugs with anticholinergic properties and associated beneficial effects are also under investigation.