I think that balancing econ and pre-med is perfectly possible as long as you plan accordingly and put in effort. Many people struggle with econ because they do not have the math background so I would definitely recommend that if you are going to pursue this path, then you should make sure you have a fairly strong math background. I know that any people might be worried about the lack of overlapping classes. I don't think this should be a huge issue. Premed requires 2 sem of bio + lab (3 cu), 2 sem physics + lab (3 cu), 2 sem general chem + lab (3 cu), 2 sem orgo (2 cu) and orgo lab (1 cu). If you do about 1.5 cu (one science course + lab) worth of pre-med requirements each semester, then you should be fine