<s>[INST] My dad has been advised to take metpure xl 50. Before sleeping he took a tablet and seems he is unable to breath properly. He says he got cold. He had undergone angioplasty 4yrs ago and had to undergo eye operation now. Since his bp did not come to normal doc prescribed this tablet [/INST] Thanks for your question on Chat Doctor. I can understand your concern. Met pure XL is having metoprolol. It is beta blocker. It blocks the beta receptor in the body. Beta receptors on airway are responsible for bronchodilator. So metoprolol blocks these receptors and cause bronchospasm. This is not seen in all patients but sensitive individuals tend to develop bronchospasm after metoprolol. So in my opinion, you should consult his doctor and change this met pure XL. Hope I have solved your query. Wishing good health to your father. Thanks. </s>