Good morning! The only side effect I had was dizziness. It happened about 2 weeks in, for a couple of weeks, then went away. I have been lowered from 5mg to 2.5mg, because my gradient went down so much in the first 60 days-which is a good thing! I was worried a few weeks ago because my blood pressure got really high-like 190/105! It was a Saturday and I thought I couldn't reach anyone but then I decided to call my cardiologist's office and got his answering service and he called me, so I would recommend that if there is an urgent problem. There is also a 24/7 line for problems through the specialty pharmacy I think. I accidentally drank something with grapefruit peel extract in it, so called and the answering service put me through to a pharmacist. I hope you feel great and don't need to call anyone! 🙂