Hi L, ask the seller what the percentage of KI (potassium iodide) and I2 (elemental iodine) is. Lugols is 10% KI, and 5% I2 in 100ml water, (this is standard Lugols solution). If the seller doesn't know, don't buy from them.
Using standard Lugols solution, the I2 per drop is 6.25mg. This is using a horizontal drop from a standard 1ml eye dropper.
8 drops of standard lugols will give you 49-50mg of I2.