Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Totally worthless... save your money.

The bottle has no markings on it that say the strength of the solution. I really cannot tell if it has any in there. They probably don't want a lawsuit since potassium iodide is a very strong chemical, but this may be so weak, the solution so slight as to be ineffective.If you plan to dose more than one person, I would seek a solution elsewhere.