a drug dosage calculation system includes a hand held , battery operated computing device for use by nurses and other clinical personnel to make calculations pertaining to the drug administration rate and the corresponding flow rate settings of iv systems that are used for intravenous administration of fluids to a patient . flow rate setting , drug dose rate , drug amount and the amount of iv solution into which the drug is diluted are the primary variables used in such calculations . a keyboard is used to supply data to a computation device that computes the unknown quantity . a display device displays the data input to the computer and also displays data calculated for the unknown variable .