Immediate hypersensitivity reactions may occur. Discontinue immediately & substitute alternative therapy if paradoxical bronchospasm occurs. Patients predisposed to narrow-angle glaucoma. When using higher doses than recommended, carefully assess risk/benefit in patients w/ insufficiently controlled DM, recent MI, severe organic heart or vascular disorders, hyperthyroidism, phaeochromocytoma, or w/ 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 more prone to GI motility disturbances. Immediately consult a physician in case of acute, rapidly worsening dyspnoea. Prolonged use. Concomitant use w/ other sympathomimetic bronchodilators. May lead to positive results (w/ regard to fenoterol) in tests for non-clinical substance abuse eg, athletic performance enhancement (doping). Dizziness, tremor, accommodation disorder, mydriasis & blurred vision during treatment may affect ability to drive or use machines. Pregnancy (especially 1st trimester) & lactation. Not recommended in childn ≤12 yr.