How many teaspoons is 50 mgs?

Answer 1

You can not equate a unit of volume (the teaspoon) with a unit of mass (the mg) because it depends on what you are measuring (its density).

Another answer:

The volume of a particular weight will vary depending upon the density of the item being measured. You are also looking for a very small volumetric measurement. For example, a teaspoon of water weighs approximately 5 grams or 5000 mg, so 50 mg would be about 1/100 of a teaspoon - not easily measured.