Ever wonder why the pithily titled class of drugs called beta-blockers can help fight off heart attacks as well as panic attacks? Well, thanks to the SciShow channel on YouTube, wonder no more.

As host Hank Green explains, it’s all a matter of location, location, location. Beta-blockers, ahem, block the chemicals norepinephrine and adrenaline from working their mojo. As Medical Daily has previously detailed, adrenaline and its partner trigger a multitude of changes in the human body, depending on which cells they come into contact with. These changes in the cardiovascular system, typically part of the “flight-or-flight” response, or sympathetic nervous system, include increased blood pressure.

Unfortunately, and especially in people with preexisting heart issues, sustained high blood pressure can be disastrous since it can scar and clog the arteries that pump blood to the heart and eventually lead to a heart attack — beta-blockers then help people keep their blood pressure in check. And while a jolt of adrenaline may be great in life-threatening situations, it’s much less appreciated and healthy when it constantly happens as a result of too much or unwarranted anxiety. So while beta-blockers don’t treat the actual source of anxiety, they do prevent its worst physical symptoms from showing up. In either case, they do this by occupying the beta adrenoceptors reserved for norepinephrine and adrenaline.

For more on how beta-blockers pull off this chemical feat without accidentally turning on our fight-or-flight response, watch the video above.