 [ Symptoms ] could my sister be schizophrenic  last year my sister was diagnosed with bipolar disorder she started taking lithium and was acting more normal for a while however she has started acting crazy again she lies about everything thinks she is psychic takes everything someone says about themselves and applies it to herself and thinks everyone is out to get her right now she will not drink water bc she thinks the fbi is trying to poison her do you think she could have been misdiagnosed and if yes what should i do [ Disease ] see your doctor for a referral to a cardiologist so that your heart and oxygen saturation can be carefully monitored while running on a treadmill this is called a stress test while it would not be unusual for someone is heart rate to go up this high it would be comforting to know that your heart is capable of handling the load the fact that you have been active for 18 years is wonderful so i am sure you will pass with flying colors but when you are in your mid 60 is it would be good to get the official okay