Cefazolin Dilution Pharmacy Math Question

by Thomas
(VA)

Cefazolin Dilution From a Stock of 1G/5mL

Cefazolin Dilution From a Stock of 1G/5mL

Prepare 15 mL of a 50 mg/mL cefazolin dilution from a stock of 1 g/5 mL. How many milliliters of diluent and stock solution will be needed?

I am having such a hard time getting these types of calculations? I just dont get this at all?? Can you show how you worked it out?

Comments for Cefazolin Dilution Pharmacy Math Question

Average Rating starstarstarstarstar

Click here to add your own comments

Rating
starstarstarstarstar
Answer
by: Anonymous

You can find your answer this way..
1g=1000mg you want all units to be the same before you start equations.

Once you convert..
15mL x 50mg/1mL x 5mL/1000mg= 3.75mL of your stock needed.
To find dilution simply subtract the 15mL you started with from the quantity needed..
15mL-3.75mL=11.25mL

Rating
starstarstarstarstar
Use the Equation: Density = Mass/Volume
by: Anonymous

Pharmacy work involves being able to create solutions or dilutions with a variety of different medications.

In some cases, these are not as easy as simply pulling our jars and bottles and measuring an amount.

In some cases, the stock solution may be much stronger than the necessary dilution calls for; this means that as a pharmacy technician dealing with medication you need to be able to make the necessary dilution.


Start by looking at everything you are going to need.

You need a 15 mL Cefazolin solution. The stock medication Cefazolin is presented in a 1g/5mL stock strength.

The solution however, requires a 50mg/mL Cefazolin solution dilution.

In order to complete the dilution you need to figure out how much Cefazolin you need to add to how much of the dilution solution in order to create the necessary 15mL solution.

There are several different ways to answer this problem; the easiest way will be to run the calculations in terms of density, mass, and volume.

The basic formula you will need is:

Density = Mass/Volume



Step 1: Set up the first equation. Take the following pieces of data: the final solution amount or volume 15mL and the density of the stock solution within the final solution, which is 50mg/mL.



Density = 50mg/mL

50mg/mL = Mass/15mL

Volume = 15mL



Step 2: You want to remove the mL from each side of the equation. You do this by multiplying by 15mL on each side.



This leaves you with Mass = 50mg * 15, which gives you 750mg. This means that the final amount of the stock solution in the final solution is 750mg. This will give you the 50mg/mL dilution.



You still need to determine how much of the stock solution is necessary to obtain this amount. This brings you to the second equation. You will still be working with density.



Step 3: Density = Mass/Volume. In this equation, you have the density 1g/5ml = 0.75g/volume.



Step 4: Multiple each side so that the equation becomes Volume = Mass/Density. The 1g/5ml will convert into a decimal of 0.2.



Step 5: This gives you the following equation:

Volume = 0.75/0.2.

This gives you a volume of 3.75mL of the stock solution is necessary along with 11.25mL of the solution being used for the dilution to create the ratio of 50mg/mL of the stock drug in the final 15mL solution.

Click here to add your own comments

Join in and write your own page! It's easy to do. How? Simply click here to return to Pharmacy Tech Math Questions.

Back to Home

[?]Subscribe To This Site
  • XML RSS
  • follow us in feedly
  • Add to My Yahoo!


Didn't find what you were looking for? Use the box below to search this entire site.

Custom Search



Recent Articles

  1. How many days will a 12 fl oz bottle last at 1 tablespoon by mouth three times daily?

    Feb 17, 18 11:24 PM

    How many days will a 12 fl oz bottle of medication last if a patient takes 1 tablespoonful by mouth three times daily?

    Read More

  2. Prior Authorization Rx Mandated to Different Pharmacy, New Pharmacy Wont Disclose Any Info, Cites HIPAA

    Feb 17, 18 11:17 PM

    Hi, I have seen it starting to occur where my company receives an RX from an office, we obtain prior authorization approval only to learn it is mandated

    Read More

  3. Local, Privately Owned Pharmacy Closed, and ALL Records/Rxs Transfered to Chain. HIPAA Violation?

    Feb 17, 18 11:08 PM

    My local, private pharmacy closed. No notice was given to customers/patients prior to the closure. The pharmacy owner took it upon himself to transfer

    Read More

  4. Pharmacy Tech Loudly Embarasses Customer: Did Tech Violate HIPAA Law?

    Feb 17, 18 10:54 PM

    I recently walked into a major grocery chain's pharmacy. The tech that took my prescription, looks at it and very loudly said are you trying to lose weight?

    Read More

  5. Days supply Norco 60 pills 1 every six hours as needed

    Feb 15, 18 05:34 PM

    I have a prescription for Norco, the amount of pills is sixty. I take one every six hours as needed. I filled the prescription on 10/9/17. Today is 11/3/17.

    Read More

  6. Days Supply Question: Cosentyx 90 day supply - How many syringes will be dispensed?

    Feb 15, 18 05:15 PM

    How many syringes would you get on a 90 day supply of Cosentyx?

    Read More

  7. Days Supply Question: Amoxicillin 500mg #42 - One cap po every 8 hours

    Feb 15, 18 05:04 PM

    What is the day supply for the following? Amoxicillin 500mg #42: i cap po q8h

    Read More

  8. Eye Drop Days Supply

    Feb 09, 18 03:01 PM

    Eye Drop Days Supply - This page includes how entering the correct days supply when first filling a new rx for eye drops can prevent some potential problems for future refills. Also, a handy chart is…

    Read More

  9. When Would a Tech Perform Temperature Conversions?

    Feb 08, 18 11:36 PM

    when would a pharmacy technician need to perform temperature conversions?

    Read More

  10. How do you figure Days Supply for BD Needles (Pen Needles and such)

    Feb 08, 18 11:07 PM

    How do you figure days supply for the BD Pen needles?

    Read More

  11. What is the correct way to bill an insurance company for a taper?

    Feb 08, 18 10:10 PM

    What would be the correct way to submit the days supply to the patient's insurance for a tapering medication? For example, if the rx says zolft 25mg

    Read More

  12. Norco 40 pills 2 po every 4 hours or 1 po every 6 hours - What is days supply?

    Feb 07, 18 10:18 PM

    I got script of 40 norco; I broke my pelvis. The directions on the first two scripts said one pill every 6 hrs, enough to last 10 days. Now I started

    Read More

  13. How do you figure Days Supply on an Albuterol Nebulizer Solution prescription?

    Feb 06, 18 05:16 PM

    What is the days supply for Albuterol 2.5ml vials x 25 vials, with a sig of 1 vial via nebulizer qid?

    Read More

  14. Pharmacy Technician Pay Raise

    Feb 06, 18 05:10 PM

    Pharmacy Technician Pay Raise - Here are some general strategies you can use to ask for a well-deserved pay raise. Some of these strategies include: being a good employee, becoming nationally certifie…

    Read More

  15. Pharmacy Tech Sample Resume

    Feb 06, 18 04:46 PM

    Pharmacy Tech Sample Resume - This page displays a sample resume of a pharmacy technician, and shows an example of how it could or should be laid out. It's important to highlight the pharmacy setting…

    Read More