I started taking these in February 2024 to prevent future UTIs. I didn’t take them daily, but rather a few days a week. I started noticing I was having heart palpitations, and chest pain sporadically and indigestion all the time. In mid March I called my doctor and when I told of my symptoms he said to go to ER because those could be signs of a heart attack. All tests were clear at ER and I was released but recommended to see a cardiologist for follow up. I had a calcium test which showed 0 blockage and an electrocardiogram which showed nothing abnormal. I quit taking the D-Mannose for about 3 weeks because I honestly was just busy and forgot about them. Last night I took 1 capsule and woke up with heart palpitations which I haven’t had at all in 3 weeks. I never realized this was the cause for the issue I was having. I took a total of 13 capsules and now after insurance, still owe over 3,000.00 worth of medical bills. I want other people to know to be very cautious and if you start having heart palpitations, it is highly likely that they are related to D-Mannose.