A tsp of salt is 3.5 g of sodium. Plus, you get sodium from food, too, right. That’s a lot of salt and is going to result in a lot of thirst and urination.
When you drink the (mild) diuretic, you’re pissing out your sodium and water. This lowers your blood pressure like during an extended fast. So then you drink salt water, making you thirsty, and repeat the process all over again the next day.
I’m not a doctor, but if I were you I wouldn’t consume so much sodium. If you reduce it gradually, your body will begin to conserve and balance it out, so you don’t just piss it out during the fasting phase. Just make sure your food has enough sodium and eat normally.
(Not a doctor, this is not medical advice, consult your physician, etc etc.)
i mean, the obvious first step for me would be to cut the diuretic. Not sure if you’re addicted to it, but diuretics and long term fasting are not such a good idea. I’m sure you wanted a solution other than this, but a diuretics job is to expel water and thus electrolytes from your body. Replacing salts (which also include potassium and to a lesser extent calcium and magnesium) while you have this substance in your system is a futile cause as your body will keep trying to expel everything you are putting in.
I would suggest switching to coffee but i dont even do that myself and it is technically still a diuretic on its own so perhaps, even for a few days, try dropping the MATE drink all together and see if you at least get an improvement in feeling.