I was in er due to low potassium from blood pressure drug chlorlithidone to find also i was over medicated on synthroid (thyroxine) to how long till side eff gone?

See below: Your potassium can be corrected in 24 hours with resolution of symptoms, if any. Thyroid hormone lasts longer. You may see benefit within days but it takes six weeks to fully equilibrate. Ask you doctor to switch you from Chlorthalidone which is famous for causing low potassium to a combination of hydrochlorothiazide/triamterene. This is just as inexpensive and avoids low potassium.

Resolve quickly: Hyperthyroidism can also lower blood potassium. Some people taking Chlorthalidone need extra potassium, others don't. If your synthroid (thyroxine) dose is correctly adjusted, and if you take some extra potassium, you should be fine. If you stick with the chlorthalidone, you should use rx potassium (can't do it with bananas). May be best to use another BP medication.

Not good BP med: Chlorthalidone is a terrible blood pressure medication and can cause increases in glucose, predisposition to diabetes, and high levels of cholesterol and triglycerides. There are many inexpensive and effective blood pressure alternatives which are much less potentially toxic.