Complex sentence: Rarely occurring, but of importance, are allergic reactions of paradoxical bronchospasm, urticaria, angioedema, hypotension, and collapse, while high doses may cause hypokalaemia (low potassium levels), especially in patients with renal failure and those on certain diuretics and xanthine derivatives.
Split into simpler sentences: Rarely occurring, but of importance, are allergic reactions of paradoxical bronchospasm, urticaria, angioedema, hypotension, and collapse. High doses may cause hypokalaemiawhich are of concern in patients with renal failure and those on certain diuretics and xanthine derivatives.