What can cause frequent heart palpitations and how can i stop them??no past heart issues

Come and go: Everyone has palpitations sometimes-they're not necessarily abnormal. Some factors that may contribute: caffeine, nicotine, alcohol, lack of sleep, stress. Certain meds(even over the counter) & electrolyte imbalance (as from diarrhea, vomiting, excessive sweating, and dieting). Lying quietly, especially face down or left side down will cause you to feel them more. If still troublesome, seek help.