MG and MCG are metric subunits of the gram and are used to measure mass or weight. For instance, a milligram is 1/1000 of a gram, whereas, a microgram is equal to 1 millionth of a gram and it is one of the smallest units of measure. These measurements are mostly observed with the medications prescribed by a physician.
An example would be Tylenol 500 mg or levothyroxine 125 mcg. A good understanding of the dosage requirements can help prevent medication errors. The milligram is the more commonly used unit of measure due to its larger size. It is also the unit of the amount used on food labels for representing the breakdown of vitamins, minerals, and other nutritional values in food products. These measurements are also used in microbiology and testing.
MG and MCG might not mean anything to you if you don't know what they actually stand for and their uses. MG and MCG are the acronyms for Milligrams and Micrograms respectively. Both milligram and microgram are used during measurement of some materials, basically to calculate their mass. The glaring thing about the two is that, milligrams use grams as the basis of its measurement, micrograms also use grams as the basis of its measurement, they are used to measure objects that are as small as drugs like most antibiotics.
The micro part shows that it is used to measure objects that are considerably lower in size, while the milli part shows it measures objects with larger size compared to micro. Micrograms can be regarded as the smallest units of measurement, and a microgram is equal to 0.001mg, which shows microgram is smaller in terms of value than milligram.