How many mL are typically needed for a 500 mg dose of amoxicillin?

To determine the correct volume of liquid needed for a 500 mg dose of amoxicillin, one must understand the concentration of the amoxicillin solution being used. Common concentrations of amoxicillin suspensions are 125 mg/5 mL or 250 mg/5 mL.

In this case, if the concentration is 250 mg per 5 mL, you would set up a proportion to find out how many mL would be needed for a 500 mg dose. Since 500 mg is double 250 mg, it would require double the volume: 5 mL multiplied by 2 equals 10 mL.

However, if the concentration were different, such as 125 mg per 5 mL, you would first find out how much volume is needed for 1 mg by dividing: 5 mL by 125 mg gives you 0.04 mL per mg. For 500 mg, you would then multiply 0.04 mL by 500 mg, resulting in 20 mL.

In this instance, knowing the concentration helps to determine that if the required volume is accurate and based on a typical concentration of the suspension used, the answer was derived as 4.0