Cromoglicate sodium

General information

Cromoglicate disodium salt (cromoglicate sodium) is available as a powder for inhalation. Each capsule contains 20 mg. The usual dose is 1 capsule inhaled four times daily. It is also dispensed in a multidose-pressurized aerosol delivering 1 or 5 mg per actuation. A 1.0% nebulizer solution (20 mg dissolved in 2 ml of distilled water) is also available. It is nebulized over 15 minutes and has the same effect as 20 mg given as a powder [ ]. Cromoglicate is taken regularly in chronic asthma and when it is effective it improves symptoms and lung function and reduces the need for bronchodilators. It has a steroid-sparing effect and should be tried before inhaled steroids are used, especially in children. It is a prophylactic drug and is not effective in acute asthma.

A liquid formulation is also available for use in rhinitis and ocular conditions. When applied topically to the eye cromoglicate is effective in the treatment of vernal keratoconjunctivitis (vernal catarrh, spring catarrh), allergic conjunctivitis, and hay fever.

Cromoglicate inhibits mast-cell degranulation and histamine release induced by phospholipase A ₂ , but does not interfere with the interaction of antigen and reaginic antibodies. Evidence is accumulating that it has an important stabilizing action on leukocytes, apart from mast cells, such as neutrophils, eosinophils, and monocytes, and that it also affects nerve reflexes in the lung [ ].

The overall incidence of adverse reactions was about 2% when using inhaled cromoglicate [ ]. Most of the observed adverse reactions are mild and transient and do not require withdrawal of therapy. Adverse reactions such as laryngeal edema, swollen parotid glands, bronchospasm, joint swelling, nausea, cough, headache, nasal congestion, rash, and urticaria have been reported in only one in 10 000 patients [ ]. The American Academy of Allergy and Immunology reported two 10-year safety reports involving 424 and 85 patients. These emphasized the safety of long-term treatment with cromoglicate. The only serious adverse effects were three cases of pulmonary infiltration and eosinophilia [ ]. In another series of 375 patients, only eight experienced adverse reactions; these included dermatitis with pruritus, myositis, and gastroenteritis [ ].

While no systemic or severe adverse reactions have been attributed to ocular cromoglicate even after as long as 8 months of therapy, transient local stinging and burning have been reported in 13–77% of patients who used the original formulation of this drug, which contained 2-phenylethyl alcohol as a preservative. These effects regressed during continued treatment and can vary greatly depending on both the individual and the underlying disease. Ocular cromoglicate without 2-phenylethyl alcohol has been reported to be more effective than formulations that contain this preservative; stinging, leading to increased lacrimation, dilutes the drug and reduces the time for which it is retained in the conjunctival sac. The desired topical effects of cromoglicate are therefore reduced if it is formulated with 2-phenylethyl alcohol.

Organs and systems