Pre-workout supplements can be a great way to give you an extra boost before hitting the gym, but they come with some risks. Taking too much pre-workout can cause side effects such as nausea, dizziness, headaches, increased heart rate and blood pressure, dehydration and even kidney damage in extreme cases. It is important to understand that pre-workouts contain various stimulants which can quickly drive up your heart rate if taken in large amounts or for long periods of time. If you experience any of these symptoms it’s best to stop taking them immediately and see a doctor for further medical advice. Additionally, if you are pregnant or breastfeeding it is highly recommended that you avoid taking pre-workouts altogether as there is not enough research on their safety during this period. Finally, make sure to always read the label carefully and consult with your doctor before taking any new supplement – especially when it comes to something like pre-workout!