countries erdosteine in approved for the treatment of bronchiectasis. Safety profile Data from post marketing surveillance confirm that erdosteine is well tolerated, with an excellent safety profile. Frequency and severity of adverse effects in clinical studies (more than 2300 patients in more than 70 clinical studies) was very low and comparable to placebo. Erdosteine is stable to hydrolysis in acid environment, so it does not have any direct effect on gastric mucus, which implies a very good safety profile. Less than 1 patient in 1.000 is expected to have gastrointestinal undesirable effects. Very rare (<1/10.000) adverse events are headache, dyspnea, taste alterations, nausea, vomiting, diarrhea, epigastric pain. Contraindications The drug is contraindicated in subjects with hypersensitivity to the active substance or to any of the excipients. It is contraindicated in subjects with active peptic ulcer. Because of a possible interference of the product with methionine metabolism, the drug is contraindicated in patients with hepatic cirrhosis and deficiency of the cystathionine-synthetase enzyme. Interaction with other medicinal products No harmful interactions with other drugs have been reported and the product can therefore be administered together with antibiotics and bronchodilators (such as beta2-mimetics and cough sedatives). References Carboxylic acids Thioethers Thiolactones Carboxamides Expectorants