What is a good over the counter substitute for lasix?

There isn't anything available over the counter that would the work that Lasix does.

Lasix (furosemide) is a loop diuretic (water pill) that prevents your body from absorbing too much salt, allowing the salt to instead be passed in your urine.

Lasix treats fluid retention (edema) in people with congestive heart failure, liver disease, or a kidney disorder such as nephrotic syndrome. This medication is also used to treat high blood pressure (hypertension).

https://www.drugs.com/lasix.html