Re: How long does lugols stay potent in the bottle? Mine is over three years old...crows brand

As long as you've kept it out of excessive light and heat, I think it would still be good. Quote I found on the web "r. Abraham's experiments that Lugol's Solution, which does contain potassium Iodide should last a very long period of time (30 years per his quote), provided it is not contaminated and kept in low light levels and at room temperature"

So stored in the dark and at a reasonable temperature, it should be fine.