Dictionary of Allergies .. Asthma and Sodium Cromolgycate

Sodium cromolgycate (SCG) has been used for the prevention of mast cell degranulation via a membrane stabilizing  effect which may be brought about by the phosphorylation of a protein that results in blocking ionic calcium transport across the cell membrane.

Prevention of the release of histamine, PGD2 and LTC4 accounts for the action of this drug on the early allergic reaction (EAR) which is IgE and mast cell-dependent. SCG suppress the actions on inflammatory cells including neutrophils and eosinophils that might contribute to the suppressive action of this drug on the allergic late reaction (LSR). It is suggested also that it may exert a neural effect, suppressing the activity of sensory nerve endings since it blocks reflex constrictor stimuli such as bradykinin, SO2, and subfreezing air. (See cromolgycate sodium). SCG is very safe prophylactic antiinflammatory medication in paediatric practice. However, in most adult asthmatics it has been replaced by inhaled corticosteroids and nedocromil sodium because of their greater potency and more effective anti-inflammatory properties[1].

Exercise induced bronchoconstriction is currently treated with inhalation of beta(2)-agonists or, as second choice, sodium cromoglycate approximately 15 min before exercise. If this proves to be insufficient then inhaled steroids should be added. Leukotriene receptor antagonists can be used in patients whose symptoms do not respond to inhaled steroids. The screening of high risk populations such as swimmers, cyclists, rowers and winter athletes is recommended by some authors[2].

References

1. Breslin, F.J., et al: The effects of cromolyn sodium on the airway

response by hyperpnoea and cold air in asthma. Am. Rev. Respir. Dis. 1980:122:11-16.

2. Billen A, Dupont L. Exercise induced bronchoconstriction and sports. Postgrad Med J. 2008 Oct;84(996):512-7