How many grains are equivalent to 90 mg of medication daily?

To determine how many grains are equivalent to 90 mg of medication, it's essential to understand the conversion between milligrams (mg) and grains. One grain is approximately 64.8 mg.

To convert 90 mg into grains, the calculation would be as follows:

[ \text{Grains} = \frac{\text{Milligrams}}{64.8 , \text{mg/grain}} ] [ \text{Grains} = \frac{90 , \text{mg}}{64.8 , \text{mg/grain}} \approx 1.39 , \text{grains} ]

Since 1 grain is equivalent to about 64.8 mg, 90 mg rounds to just over 1.39 grains. The closest whole number grain representation that aligns with this conversion is 1 grain, or "gr i".

Therefore, the correct answer, indicating that 90 mg is approximately equal to 1 grain, is confirmed by the established conversion factor and the resultant calculation. This understanding of grain to milligrams translation is crucial in the context of pharmacology, especially when dealing with medication dosages and historical measurements.