Iodine used in J.Crow's Lugol's solution is derived from mined crystals, not from shellfishApproximately 1200 vertical drops per 2 oz. containerTo use as a water purifier add 3-6 drops per liter of waterAlways fresh does not expire Equivalent to USP or Higher 2 oz Dropper Bottle Calculating Number of MG's of Iodine and Iodide per Drop of LUGOL'S 2%: Each VERTICAL "metric" drop (= 1/20 ml) is approximately 1.0 mg of iodine and 2.0 mg of potassium iodide. The Iodide portion of Potassium Iodide is about 75% so that is 1.5 mg. Therefore the total Iodine plus Iodide is 1.0 + 1.5 = 2.5 mg and 2 drops is about 5.0 mg's of iodine/iodide (2.0 mg iodine, 3.0 mg iodide). Compared to iodine and potassium iodide tablets, J.CROW'S Lugol's Solution offers big savings. Approximately 1200 vertical drops per 2 oz. container. To use as a water purifier add 3-6 drops per liter of water. Made from premium ingredients, the iodine used in J.CROW'S Lugol's Solution is derived from mined crystals from 320 million year old natural brine deposits two miles beneath the earth's surface in Western USA (one of the few places in the world where such deposits exist). Not made from shellfish. The water used is distilled, pure, New Hampshire spring water. Always fresh. Does not expire. Store at room temperature out of direct sunlight. No need to refrigerate. Be safe. Accept no substitutes. Keep J.CROW'S Lugol's Solution of Iodine on hand. Trusted Original Since 1829. Low Heavy Metal Verified. USA Sourced.