Common side effects of P2 include nausea, dizziness, headaches, dry mouth, constipation, loss of appetite, and fatigue. More serious side effects have been reported and include respiratory depression, heart palpitations, low blood pressure, and even coma and death in some cases. P2 can also interact with other medications and lead to dangerous drug interactions. It is important to speak to a doctor before taking P2 and to be aware of any potential side effects or drug interactions.