2. Rapid heartbeat
Studies have found that low blood sugar levels can cause an epinephrine or adrenaline response in the body as a form of a biological emergency system to let you know that something is wrong. In other words, your heart may start beating rapidly if your blood sugar is low as a way to tell you that you need to ‘eat sugar now!’
If you start to experience a rapid heartbeat and you are taking a medication that boosts your insulin levels, it could be a sign of low blood sugar.