Blood pressure normal heartbeat fast, clinical possible causes are hyperthyroidism, hypoglycemic reaction, carbon monoxide poisoning. 1. Hyperthyroidism: this disease refers to the clinical syndrome caused by excessive production of thyroid hormones, which is typically characterized by hypermetabolism, increased systemic excitability, etc. Clinical manifestations include tachycardia, weight loss, increased frequency of bowel movements or diarrhea. 2. Hypoglycemia: the situation refers to the plasma glucose level drops to below normal, postprandial hypoglycemia mostly occurs about 1.5~3 hours after breakfast, clinical manifestations include palpitations, sweating, hunger, tremor, and so on, and in severe cases, there will also be consciousness disorders. 3. Carbon monoxide poisoning: this refers to the body through the respiratory tract inhalation of carbon monoxide and caused by poisoning, mostly in winter. The clinical symptoms of mild poisoning include dizziness, headache, vomiting, weakness of the limbs, etc. In serious cases, cardiac arrhythmia, pulmonary edema, cerebral edema, respiratory depression, etc., and it is necessary to get out of the poisoned environment urgently for further rescue. If there are relevant situations, it is necessary to go to the hospital in time for consultation and targeted treatment.