Pharmacologic Principles (Lilley, p. 16) Pharmaceutics Pharmacokinetics Pharmacodynamics Pharmacotherapeutics Pharmacognosy Five basic principles of drug action have to do with pharmacodynamics. What are the three categories of drug administration? (Enteral, parenteral, and percutaneous) List the parenteral routes in order of fastest to slowest absorption. (IV, IM, subcutaneous, intradermal) NURSING APPLICATION: Why will it be important to Ms. Jackson for the nurse to know about pharmacology principles? Copyright © 2011 by Elsevier Inc. All rights reserved.

Pharmacokinetics: Absorption (Lilley, p. 20) The rate at which a drug leaves its site of administration, and the extent to which absorption occurs Bioavailability Bioequivalent Gender-specific medicine is a developing science that looks at how men and women perceive and experience disease, as well as how pharmacokinetics affects each gender. NURSING APPLICATION: Do you think Ms. Jackson could absorb medications differently from a younger patient? Copyright © 2011 by Elsevier Inc. All rights reserved.

Factors That Affect Absorption (Lilley, p. 20) Absorption characteristics vary according to the dosage form and route Food or fluids administered with the drug Dosage formulation Status of the absorptive surface Rate of blood flow to the small intestine Acidity of the stomach Status of GI motility Time-released capsules should never be broken apart because this can affect the absorption rate. Briefly describe absorption, focusing on how the administration route affects rate and solubility (e.g., oral drugs will not take effect as quickly as IVs). The absorption rate of a medication varies greatly depending on the route of administration. The route should never be changed without a medication order. NURSING APPLICATION: Do you think Ms. Jackson's GI system could be hampering  medication effectiveness? Why? Copyright © 2011 by Elsevier Inc. All rights reserved.

Onset, Peak, and Duration (Lilley, p. 26) The time it takes for the drug to elicit a therapeutic response Peak The time it takes for a drug to reach its maximum therapeutic response Duration The time a drug concentration is sufficient to elicit a therapeutic response Onset of drug action with parenteral administration is faster but of shorter duration. If the drug is ordered as part of a preoperative or preprocedure order, it must be given at the correct time to ensure that the peak effect will occur when it is needed. NURSING APPLICATION: Why will the duration of a medication matter when giving meds to Ms. Jackson? Copyright © 2011 by Elsevier Inc. All rights reserved.

Ways Drugs Produce Therapeutic Effects (Lilley p. 28) Once the drug is at the site of action, it can modify the rate (increase or decrease) at which the cells or tissues function A drug cannot make a cell or tissue perform a function it was not designed to perform The duration of effects is determined largely by the combination of metabolism and excretion. NURSING APPLICATION: Since Ms. Jackson has a urinary infection, how would her fluid intake affect the therapeutic effect of her medication? Copyright © 2011 by Elsevier Inc. All rights reserved.

Copyright © 2011 by Elsevier Inc. All rights reserved. Monitoring (Lilley p. 30) Therapeutic index Drug concentration Patient’s condition Tolerance and dependence Interactions Adverse drug effects Therapeutic drug monitoring is very important for geriatric and pediatric patients. NURSING APPLICATION: Why do you think that Ms. Jackson's condition will affect the drug concentration of the antibiotics? Copyright © 2011 by Elsevier Inc. All rights reserved.

Fractions: Fundamental Rules (Gray Morris p. 11) The value of a number is unchanged when the numerator and denominator are multiplied or divided by same number Example: Change a fraction to lowest terms by dividing numerator and denominator by the largest whole number that will divide into both evenly Dosage calculation is extremely important to ensure the correct dosages for patients. NURSING APPLICATION: When will it be important to know what fraction of a medication to give? Copyright © 2011 by Elsevier Inc. All rights reserved.

Fractions: Reducing (Gray Morris p. 12) Should always be reduced to lowest terms Numerator and denominator are each divided by the largest number by which they are both evenly divisible Example: Remember that medications come in many different strengths and amounts. NURSING APPLICATION: If Ms. Jackson were to take one half of the loratadine 10 mg, how many milligrams would she be taking? Copyright © 2011 by Elsevier Inc. All rights reserved.

Fractions: Dividing (Gray Morris p. 16) Invert the second number (turn it upside down) and then multiply. Reduce if necessary. Note: Change mixed numbers to improper fractions before performing division steps. NURSING APPLICATION: This calculation will be important as the nurse determines the total number of tablets to give a patient. Copyright © 2011 by Elsevier Inc. All rights reserved.

Decimals: Dividing by a Decimal (Gray Morris p. 30) Move the decimal in the divisor to the right until the number is a whole number. Then move the decimal in the dividend the same number of spaces. Caution: each decimal expression with a value less than 1 is preceded by a leading zero to emphasize the presence of a decimal, according to national patient safety standards (ISMP and TJC) To divide by 10, 100, or 1,000, move decimal to the left one place for each zero in the divisor. NURSING APPLICATION: What can happen if the decimal is in the wrong place as you do this calculation? Copyright © 2011 by Elsevier Inc. All rights reserved.

Decimals: Changing from Fractions (Gray Morris p. 34) Rewrite fraction in division format Divide the numerator by the denominator and add zeros as needed Method can be used to compare fraction size To convert a decimal to a fraction, write the decimal number as a whole number in the numerator of the fraction, and express the denominator of the fraction as a power of 10. Place the number 1 in the denominator of the fraction, and add as many zeros as there are places to the right of the decimal point. Reduce to lowest terms if necessary. (See Reading and Writing Decimals, p. 22.) NURSING APPLICATION: When do you think application of changing decimals to fractions would be important? Copyright © 2011 by Elsevier Inc. All rights reserved.