What indicates the quantity of a tablet in medication instructions?

The quantity of a tablet in medication instructions is indicated by the abbreviation "tab." This term is short for "tablet," which refers specifically to solid pharmaceutical forms of medication that are typically swallowed whole. When encountering medication instructions, "tab" signifies that the medication is given in tablet form and provides clarity on how many tablets should be taken.

The other terms have different meanings: "no." could refer to "number" but is not a standard abbreviation for quantity in this context. "cap." stands for "capsule," which is another form of medication but does not pertain to tablets. "mg" indicates milligrams, which is a measure of weight rather than a count of tablets. Therefore, "tab." appropriately directs the user to the required quantity of tablets for the medication being administered.