Brief Answer: Beta Blockers Detailed Answer: Dear Mam Hi , I am Dr Anshul Varshney , I have read your query in detail , I understand your concern. I would like to know why you want to slow down your heart rate? Is it because of anxiety problems? The drugs used to control heart rate are Beta Blockers like propranolol , metoprolol. And also a few Calcium channel blockers like Diltiazem. However , Propanolol can aggravate your Asthma , so i would not recommend. Low doses of Metoprolol , if tolerated well by an asthma patient can be given. But , dose would based on Blood Pressure and Heart Rate. However , if you have anxiety problems , you can take anti anxiety drugs under your doctor's guidance. You should avoid beta blockers and calcium channel blockers , as they are made for other purpose of targeting heart rate in heart patients. Not used routinely for anxiety purposes. Many doctor's use propranolol for anxiety, but that is contraindicated in Asthma patients. This is my personal opinion based on details available here. If you still have any query you may please ask me. Stay Healthy. Dr Anshul Varshney , MD

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