1 / 11

Percentage concentration

Learn how to calculate drug concentrations, ratios, and alligations in pharmaceutical solutions with detailed examples and formulas. Improve your pharmacy math skills for accurate medication preparation and dosing.

halledward
Download Presentation

Percentage concentration

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. % w/w(weight)----------active ingredient and base have same unit of weight. 1%=1gm of active ingred per 100gm total product. 1% w/w= 1gm/100gm %v/v(volume)-------solute(active drug) and solvent(inactive base) have same unit of volume. 1% v/v=1ml/100ml %w/v(weight/volume)-------solute is in the weight grams and solvent is in volume ml. 1% w/v=1gm/100ml Percentage concentration

  2. 1.4g of phenol mixed with 9g of glycerin. What is % concentration of phenol in this product? 1.4+ 9g =10.4g part/whole x 100=% 1.4/10.4*100=13% w/w 4g KCL is dissolved in base to make total of 25ml. What is per concentration of final product?4/25*100=16%w/v 10ml glycerin is dissolved in enough water to make 73ml of final solution. Calc % of strength of glycerin. 10/73*100=14% v/v

  3. How much KCL is needed to make 240ml of a 10% solution? • 10% mix assumes 10mg mixed into 100ml of fluid • 10mg/100ml=x mg/240ml • X=24mg of kcl • 5g is how many mg? • 1000mg/1gx 5g/1=5000mg • 120mg to g • 1000mg/1g x 120mg/x= g • x=1000x/120=.120g

  4. alligations • Using 2 different concentrations of a drug to arrive at final concentration somewhere between the 2 in stock. • Dr orders 30g of 15% hydrocortisone cream. Pharmacy has cream in 20% and also 2%. Alligation will combine these to get 30gm, of 15%. • See board pg158-------

  5. Ratio concentrations Normally this uses epinephrine or potassium permanganate. You must memorize------- 1:1000------1mg/ml 1:100--------10mg/ml 1:10---------100mg/ml Rx is 3mg of epi. Pharm stock is 1:100 solution. How may ml will be given? 10mg/ml= 3mg/xml 10x mg=3mg X=.3ml

  6. Rx 2.5ml inj of 1:1000 epi is given. How much drug did pt get? • 1:1000=1mg/ml • 1mg/ml=x mg/2.5ml • X =2.5mg

  7. Parenteral calculation • Done for IV drips. This has greater risk of immediate pt harm if wrong. • Flow rate=vol/time • Pt gets 1L of IV sol over 3 hours. What is flow rate? • Flow rate=1000ml/3hrs • Fr=333ml/hr --- this means 5.55ml/min

  8. How many hours will 1L of D5W last when flow rate is 125ml/hr? • Time=vol/rate • time=1000ml/125ml • Time=8hr • Vol=time *rate • How many ml needed to run IV at 60ml/hr for 12 hours? • Vol=12hrs*60mlper hour • Vol=720ml

  9. Gtt/min=volume to be infused *drip set rate/infusion time in minutes • Rx is d5w at 125ml/hr. admin set is 10gtt/ml. How many gtt/min should we use? • Gtt/min= 125ml*10gtt/60min • Gtt/min=1250/60 • Gtt/min=20.8 ~21gtt/min

  10. Gtt/min=volume to be infused *drip set rate/infusion time in minutes • 300ml of d5w given at rate of 75ml/hr. admin set gives 10gtt/ml.how many gtt/min should we use? • Gtt/min=vol infused*drip rate/infusion time(min) • Gtt/min= 75ml*10/60 • Gtt/min=750/60 • Gtt/min=12.5gtt/min ~13ggt/min

  11. https://www.youtube.com/watch?v=CujuVNn7ROY • alligations • https://youtu.be/765wpMCEy6c • Drip rate • https://youtu.be/8qDVEtrQ8a4 • Percents • https://youtu.be/xWw2pQrnztU • Powder volume • https://youtu.be/mm6jeTZV1Z0 • mEq

More Related