<p>Zafirlukast should be taken regularly to achieve benefit, even during symptom free periods. Zafirlukast therapy should normally be continued during acute exacerbations of asthma. Zafirlukast does not allow a reduction in existing steroid treatment. As with inhaled steroids and hormones (disodium cromoglycate, nedocromil sodium), Zafirlukast is not indicated for use in the reversal of bronchospasm in acute asthma attacks. Zafirlukast has not been evaluated in the treatment of labile (brittle) or unstable asthma.<br />
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Cases of Churg Strauss syndrome have been reported in association with Zafirlukast usage. A causal relationship has neither been confirmed nor refuted. If a patient develops a Churg Strauss syndrome type illness, Zafirlukast should be stopped, a re-challenge test should not be performed and treatment should not be restarted.<br />
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Elevations in serum transaminases can occur during treatment with Zafirlukast. These are usually asymptomatic and transient but could represent early evidence of hepatotoxicity.<br />
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If clinical symptoms or signs suggestive of liver dysfunction occur (e.g., nausea, vomiting, right upper quadrant pain, fatigue, lethargy, flu-like symptoms, enlarged liver, pruritus and jaundice), the serum transaminases, in particular serum ALT, should be measured and the patient managed accordingly. A decision to discontinue Zafirlukast should be individualized to the patient&rsquo;s condition, weighing the risk of hepatic dysfunction against the clinical benefit of Zafirlukast to the patient.</p>