im 30 yr old, female, height 5'1 and weight 51.8>.>. i have a tachychardia for almost 5 months now and im taking inderalfor the first two months but witout progress.. my cardio gave me concor 2.5 mg for two months now but my bp becomes low.. my internal medicine doctor told me to take concor EVERY OTHER DAY.. im doing it for 3 days noe, with one day interval but my tachychardia become worst that i need to run to ER every now and then,, what should i do?? we will do halter this week. thank u