A teaspoon can hold about 5 grams. This is equal to 500 milligrams.

So, if there are 500 mg in 1 teaspoon, 1/4 teaspoon would contain one fourth of this value;

1 x 500 = 125

4

Hence, there are 125 milligrams in one fourth of a teaspoon.

So, if there are 500 mg in 1 teaspoon, 1/4 teaspoon would contain one fourth of this value;

1 x 500 = 125

4

Hence, there are 125 milligrams in one fourth of a teaspoon.