Palpitations are a common reaction to MDMA. It's hard to address the question without knowing all the info. The main thing is to make sure that he is safe, we basically treat the symptoms as they arise. If he starts to have any more signs and symptoms of cardiac issues such as chest pain or dizziness, if he is running a high fever or having seizures then he will require further emergency treatment. What pressure seems a little bit low, that could be caused from dehydration or other factors but I would be Leary of giving oral fluids at this point until u know he is not having any further symptoms as seizures are a common side effect and you don't want him getting fluid in the lungs if he seizes. I'm assuming he is receiving IV fluid in the ER? Supportive care is the key.