Hypersensitivity. Immediately discontinue use if paradoxical bronchospasm occurs. Patients predisposed to narrow-angle glaucoma. Carefully assess risk/benefit especially w/ higher doses in insufficiently controlled DM, recent MI, severe organic heart or vascular disorders, hyperthyroidism, phaeochromocytoma, pre-existing urinary outflow tract obstruction (eg, prostatic hyperplasia or bladder-neck obstruction). Patients w/ underlying severe heart disease (eg, ischaemic heart disease, arrhythmia or severe heart failure). Potentially serious hypokalaemia. Patients w/ cystic fibrosis may be prone to GI motility disturbances. Advise patients to immediately consult physician in case of acute, rapidly worsening dyspnoea. Prolonged use. Concomitant use w/ other sympathomimetic bronchodilators. May lead to +ve results to fenoterol in tests for non-clinical substance abuse (eg, doping). May cause wheezing & breathing difficulties due to benzalkonium Cl content; increased risk of adverse events in asthma patients. Avoid contact w/ eyes. Possible dizziness, tremor, accomodation disorder, mydriasis & blurred vision may affect ability to drive & use machines. Pregnancy (especially 1st trimester) & lactation.