I used to have it a fair amount, and medicate myself to avoid it a fair amount as well, and then just about exactly 20 years ago, in the span of about three days, I started feeling sick, got more and more sick, went to the doctor and discovered I had cancer, and had emergency surgery. Then I went through about six months of really awful chemotherapy.
I definitely wouldn't recommend having cancer as a cure for existential dread, but it worked for me.