Question: Why chemical factors and substances increases the heart rate? Mariola (Menorca).
Answer: The answer is not easy! Heart rate is one of the mechanisms that regulate the functioning of the heart and varies for multiple circumstances. The causes of heart rate alteration or the substances that can modify it would make up an encyclopedic list that gives an entire cardiology book. Keep in mind that any alteration in the human body (fever, fatigue, etc.) or hormones causes the heart to readjust the heart rate to meet the body's needs. Likewise, another no less dense book could be written on arrhythmias and diseases that directly affect the heartbeat. Surely you ask us this question because you have a specific example in mind. We recommend that you consult your GP, as he or she will be able to guide you the best.