Brief Answer: Refer below Detailed Answer: Hi, Thanks for consulting HealthcareMagic! There are a number of causes than cause fast heart rate like: Many heart related conditions like conduction defects, high blood pressure etc But also: Hyperthyoidism, few lung diseases, electrolyte imbalance, excessive alcohol intake drug abuse Excessive smoking Emotional stress drinking large amounts of caffeinated beverages etc. To identify the exact cause you may need some tests. But preliminarily, an EKG is required to know whether it is of serious type or not. Physical examination can exclude a lot of possibilities. Try to be calm and cool for sometime and recheck. Hope I have answered your query. Let me know if you have have any clarifications. If not, you can close the discussion and rate the answer. If you like my answers and wish me to answer in future, bring it to my attention: Dr Vasanth. Url link is as follows: WWW.WWWW.WW Wish you good health!

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