Bronchospasm allergic drug reaction

Allergic responses to drugs are mediated by the release of histamine or histamine-like substances, and they commonly present as skin rashes, particularly urticaria. More serious hypersensitivity responses include bronchospasm or the acute, explosive anaphylactic reaction with cyanosis and cardiovascular collapse. A delayed reaction known as serum sickness, although more often associated with such drugs as the penicillins and cephalosporins rather than with serum, manifests clinically 7 to 10 days after receiving the drug or serum as fever, malaise, joint pains, and urticarial skin rashes. 

The main varieties of adverse effects attributed to cimetidine relate to its antiandrogenic properties and its actions in sufficient concentrations on the central nervous system. There is also a spectrum of drug interactions, mainly attributable to inhibition of hepatic CYP isoforms, but they only have clinical consequences under special circumstances. Occasional adverse effects, which are generally minor, include bradycardia and conduction defects, thrombocytopenia, neutropenia, interstitial nephritis, mild hepatic dysfunction, and headache. Intestinal infection due to loss of the gastric acid barrier also occurs, and myalgia, fever, monoamine oxidase-Uke interactions, and neuropathies have been well documented occasionally. Allergic reactions, such as bronchospasm, have rarely been described. Anaphylaxis with recurrence on rechallenge is on record, as are asthma and skin effects. 

The manufacturers received 1100 reports of allergic reactions in the first 2 years after launch. Fatal anaphylactic and anaphylactoid reactions have been reported 10% of all reports on anaphylactic reactions in the USA named zomepirac, making it second only to the much older drug tolmetin. Hypersensitivity reactions are characterized by hypotension, bronchospasm, and serious respiratory distress, with or without oropharyngeal edema. Type-Ill allergic reactions have also been described. 

Hypersensitivity reactions to aspirin are much more likely to occur in patients with asthma or allergic problems than in the normal population. One in 10 patients with asthma may be hypersensitive and suffer severe bronchospasm. Other reactions are urticaria, angioedema and rhinitis. The incidence of hypersensitivity to ibuprofen is much lower than with aspirin, but the drug should be avoided by patients with asthma and individuals who are sensitive to aspirin, unless they have taken ibuprofen before without problems. 

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