Trying to buy health insurance on your own and have gallstones? You'll automatically be denied coverage. Rheumatoid arthritis? Automatic denial. Severe acne? Probably denied. Do you take metformin, a popular drug for diabetes? Denied. Use the anti-clotting drug Plavix or Seroquel, prescribed for anti-psychotic or sleep problems? Forget about it. Trying to buy health insurance on your own and have gallstones?