Category Archives: Pharmacy

Introducing RxCalc 1.1

RxCalc 1.1When we released RxCalc 1.0 we felt the need to focus most of our effort on making sure our math was correct. We felt if the standard user interface was good enough for Apple, it was good enough for us. Since that time we’ve collected a bit of feedback, some great, some not so great, and a couple of really horrible comments that made us cringe. Fear not! We picked ourselves up off the ground, regrouped, and went to work on RxCalc 1.1. We hope you enjoy using it as much as we enjoyed developing it.

What’s New in 1.1?


  • User configurable Units of Measure
    1. Height
    2. Weight
    3. Serum Creatnine
  • Configurable Volume of Distribution
    1. Aminoglycoside
    2. Vancomycin
  • Less rigid scrolling
  • Less rigid data entry

The big addition is the user configurable Units of Measure and adjustable Volume of Distribution. These should help folks outside the United States and gives flexibility to those that would like to modify the default Volume of Distribution values. We’re also really happy with the new navigation experience. Version 1.0 was a bit rigid, we’ve changed that. You can now freely move between entry fields and scroll top to bottom with complete freedom, while the keyboard is showing.

Oh, yeah, it also has a great new icon! Courtesy of our good friend, Mr. Layne Lev.

Got Pharmacokinetics?

RxCalc IconThe year is coming to an end, so why not celebrate by purchasing a copy of RxCalc for your iPhone? There’s still time to buy before the end of the year and at $0.99 it’s a real bargain! At least we think it is.

So, what do you get for less than a buck?

  • New Start – Vancomycin and Aminoglycoside.
  • Adjustment with Levels – Vancomycin and Aminoglycoside.
  • Ideal Body Weight
  • Creatinine Clearance (CG)

That’s just the 1.0 release. We have more features planned for the next release and we’d LOVE to hear from our users, just drop us an e-mail at, it’s that easy.

If you’d like more information on RxCalc, just visit the RxCalc product page. If you’d like to purchase RxCalc, visit the iPhone App Store.

Cockcroft-Gault remains standard for pharmacokinetic calculations, for now.

A recent article in Hospital Pharmacy presented a review of literature comparing various methods used for estimating renal function and how those equations are best used when applied to drug dosage adjustments. The article, “Drug Dosage Adjustment Using Renal Estimation equations: A Review of the Literature” discusses literature surrounding the Cockcroft-Gault (CG), the abbreviated Modification of Diet in Renal Disease equation (abbrMDRD), and to a lesser extent the original Modification of Diet in Renal Disease equation. Although promising, there simply isn’t enough literature to support the use of the abbrMDRD equation in pharmacy practice. The article concludes that “although the abbrMDRD equation has many advantages as compared with the CG equation, too little research has been completed at this time to recommend the clinical use of the abbrMDRD equation in pharmacy practice.”

RxCalc currently uses the Cockcroft-Gault equation to estimate renal function for all pharmacokinetic calculations. Apple Core Labs will continue to evaluate new and emerging data, and use this information to make changes to RxCalc when deemed appropriate.