Calculation Of Oral Medication

25,780 views

Published on

0 Comments
11 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
25,780
On SlideShare
0
From Embeds
0
Number of Embeds
25
Actions
Shares
0
Downloads
278
Comments
0
Likes
11
Embeds 0
No embeds

No notes for slide

Calculation Of Oral Medication

  1. 1. Calculate with Confidence 5 th edition Gray Morris Mosby items and derived items © 2010 by Mosby, Inc., an affiliate of Elsevier Inc.
  2. 2. Calculation of Oral Medications Unit Four: Chapter 17 Mosby items and derived items © 2010 by Mosby, Inc., an affiliate of Elsevier Inc.
  3. 3. Calculation of Oral Medications: Objectives <ul><li>After reviewing this chapter, you should be able to: </li></ul><ul><li>Identify forms of oral medications </li></ul><ul><li>Identify terms on labels used in calculation </li></ul><ul><li>Calculate dosages for oral medications using ratio and proportion, the formula method, and dimensional analysis </li></ul><ul><li>Apply principles to obtain rational answers </li></ul>
  4. 4. Background: Oral Medications <ul><li>Most economical </li></ul><ul><li>Easiest to administer </li></ul><ul><li>Most common type of medication given </li></ul><ul><li>Available as solids and liquids </li></ul>
  5. 5. Forms of Solid Medications <ul><li>Tablets </li></ul><ul><ul><li>Powdered medications molded in shapes </li></ul></ul><ul><li>Caplets </li></ul><ul><ul><li>Elongated tablets coated to ease swallowing </li></ul></ul><ul><li>Scored tablets—use pill cutter </li></ul><ul><ul><li>Tablets with indented markings designed to cut and deliver ½ to ¼ what is in a whole tablet </li></ul></ul><ul><li>Note: Breaking an unscored tablet is dangerous </li></ul><ul><li>and can result in an unintended dose </li></ul>
  6. 6. Forms of Solid Medications (cont’d) <ul><li>Enteric-Coated Tablets </li></ul><ul><ul><li>Special coating protects against gastric secretions </li></ul></ul><ul><ul><li>NEVER crush EC tablets—defeats the purpose </li></ul></ul><ul><li>Sublingual Tablets </li></ul><ul><ul><li>Placed under tongue for direct absorption </li></ul></ul><ul><ul><li>NEVER swallow SL tablets—prevents desired effect </li></ul></ul><ul><li>Layered Tablets </li></ul><ul><ul><li>Layers or cores of two meds with different compatibilities or absorption components </li></ul></ul>
  7. 7. Forms of Solid Medications (cont’d) <ul><li>Time-Release and Extended-Release Tablets </li></ul><ul><ul><li>Labeled SA, LA, XL, SR, or ER </li></ul></ul><ul><ul><li>Released over a period of time </li></ul></ul><ul><ul><li>NEVER crush, chew, or break </li></ul></ul><ul><li>Capsules </li></ul><ul><ul><li>Contains powder, liquid, or oil with hard/soft gelatin coating </li></ul></ul><ul><ul><li>NEVER crush, chew, or break without consulting a pharmacist </li></ul></ul><ul><li>Others: Troches, Lozenges, Pulvules </li></ul>
  8. 8. Figure 17-1 A, Various shapes of tablets. B, Tablets scored in halves and fourths. (From Kee JL, Marshall SM: Clinical calculations: with applications to general and specialty areas, ed. 6, St. Louis, 2009, Saunders.) Figure 17-3 Pill/tablet cutter. (From Kee JL, Marshall SM: Clinical calculations: with applications to general and specialty areas, ed. 6, St. Louis, 2009, Saunders.)
  9. 9. Figure 17-4 Layered tablet. (From Clayton BD, Stock YN, Harroun RD: Basic pharmacology for nurses, ed. 14, St. Louis, 2007, Mosby.) Figure 17-5 Timed-release capsule. (From Clayton BD, Stock YN, Harroun RD: Basic pharmacology for nurses, ed. 14, St. Louis, 2007, Mosby.)
  10. 10. Figure 17-6 Various types of capsules. A, Lanoxicap. B, Different types of capsules. (A from Mosby’s drug consult 2003, St. Louis, 2003, Mosby. B courtesy Amanda Politte, St. Louis.) Figure 17-7 Forms of solid oral medications. Top row, Uniquely shaped tablet, capsule, scored tablet; bottom row, gelatin-coated liquid capsule, extended-release capsule, enteric-coated tablet. (From Potter PA, Perry AG: Fundamentals of nursing, ed. 7, St. Louis, 2009, Mosby.) Figure 17-8 Various sizes of gelatin capsules. (Courtesy Oscar H Allison. From Clayton BD, Stock YN, Harroun RD: Basic pharmacology for nurses, ed. 14, St. Louis, 2007, Mosby.)
  11. 11. Points to Remember <ul><li>Converting dosages from apothecary to metric can result in discrepancies </li></ul><ul><ul><li>ASA (CF: gr i = 60 to 65 mg) </li></ul></ul><ul><li>10% rule—no more than 10% variance should exist between dose ordered and dose administered </li></ul><ul><li>Capsules are administered whole </li></ul><ul><li>Tablets are available in different strengths </li></ul>
  12. 12. Points to Remember (cont’d) <ul><li>It is safer to give whole tablets equal to the dose than to cut tablets </li></ul><ul><li>Maximum number of tablets or capsules used to deliver a dose is usually three (3) </li></ul><ul><ul><li>Exceptions exist, such as some HIV meds—always double-check dosage </li></ul></ul><ul><li>Some measures and units such as mEq do not convert between metric and apothecary </li></ul>
  13. 13. Examples <ul><li>The following three examples are based on </li></ul><ul><li>this order: </li></ul><ul><li>Give: Digoxin 0.375 mg p.o. daily </li></ul><ul><li>Available: Digoxin in scored tablets of 0.25 mg </li></ul>
  14. 14. Ratio and Proportion Method
  15. 15. Formula Method
  16. 16. Dimensional Analysis Method
  17. 17. Additional Example <ul><li>The following example is a dimensional analysis item that incorporates a conversion and is based on this order: </li></ul><ul><li>Give: Nitroglycerin gr 1/150 sublingual p.r.n. chest pain </li></ul><ul><li>Available: Sublingual nitroglycerin tabs labeled 0.4 mg </li></ul>
  18. 18. Dimensional Analysis with Conversion
  19. 19. Variations of Tablet/Capsule Problems <ul><li>To determine the number of tablets needed over a period of days, multiply doses per day by the number of days </li></ul><ul><ul><li>Example: Valium 10 mg p.o. q.i.d for 7 days. Tablets available are 5 mg tablets. </li></ul></ul><ul><ul><li>Multiply 5 mg  2 for each dose = 2 tablets per dose </li></ul></ul><ul><ul><li>Multiply 2 tablets  4 for 4 doses/day = 8 tablets/day </li></ul></ul><ul><ul><li>Multiply 8 tablets per day  7 to find number needed for 7 days = 56 tablets </li></ul></ul>
  20. 20. Variations of Tablet/Capsule Problems (cont’d) <ul><li>Determining dosage to be given each time </li></ul><ul><ul><li>Example: A client is to receive 1 g of a drug daily in four divided doses </li></ul></ul>
  21. 21. Calculating Oral Liquids <ul><li>For clients with dysphagia (difficulty swallowing) or a nasogastric, jejunostomy, or gastrostomy tube </li></ul><ul><li>For infants and young children </li></ul><ul><li>Types—may contain multiple meds </li></ul><ul><ul><li>Elixir—meds dissolved in alcohol and water—aromatic </li></ul></ul><ul><ul><li>Suspension—meds dissolved in water </li></ul></ul><ul><ul><li>Syrup—one or more meds dissolved in sugar and water </li></ul></ul><ul><li>Note: NEVER give oral liquids by IV–FATAL! </li></ul>
  22. 22. Measuring Oral Liquids <ul><li>Standard calibrated measuring cup </li></ul><ul><ul><li>Metric, apothecary, or household measure </li></ul></ul><ul><ul><li>Place on flat surface and view at eye level </li></ul></ul><ul><ul><li>Pour with label facing you so it can be read </li></ul></ul><ul><li>Calibrated droppers </li></ul><ul><ul><li>Use only dropper supplied with medication </li></ul></ul><ul><li>Calibrated oral syringes (tsp/mL marks) </li></ul><ul><ul><li>Used for accuracy of liquid doses (e.g., 6.4 mL) </li></ul></ul><ul><ul><li>Pour medication in cup and draw up into syringe </li></ul></ul><ul><ul><li>NEVER use oral syringes for parenteral meds </li></ul></ul>
  23. 23. Figure 17-9 Reading meniscus. The meniscus is caused by the surface tension of the solution against the walls of the container. The surface tension causes the formation of a concave or hollowed curvature on the surface of the solution. Read the level at the lowest point of the concave curve. (From Clayton BD, Stock YN, Harroun RD: Basic pharmacology for nurses, ed. 14, St. Louis, 2007, Mosby.) Figure 17-11 Oral syringes. (Courtesy Chuck Dresner. From Clayton BD, Stock YN, Harroun RD: Basic pharmacology for nurses, ed. 14, St. Louis, 2007, Mosby.) Figure 17-10 Medicine dropper. (Modified from Clayton BN, Stock YN, Harroun RD: Basic pharmacology for nurses, ed. 14, St. Louis, 2007 Mosby.) Figure 17-12 Filling a syringe directly from medicine cup. (Modified from Clayton BD, Stock YN, Harroun RD: Basic pharmacology for nurses, ed. 14, St. Louis, 2007, Mosby.)
  24. 24. Measuring Oral Liquids (cont’d) <ul><li>Do NOT confuse dosage strength with total volume in container </li></ul><ul><ul><li>Example: May contain 100 mL in bottle, but strength will be something like 125 mg in 5 mL </li></ul></ul><ul><li>Calculations are performed in the same manner as for solid forms of medicines </li></ul>
  25. 25. Order: Dilantin 200 mg p.o. t.i.d. Available: Dilantin suspension 125 mg in 5 mL

×