Drug Action: Pharmaceutics, Pharmacokinetics, and Pharmacodynamic Phases
DRUGS TAKEN BY MOUTH GOES THROUGH THESE 3 PHASES AS DRUG ACTIONS OCCUR: (LIST IN THEIR ORDER)
PHARMACEUTIC,PHARMACOKINETIC, AND PHARMACODYNAMIC
IN THIS PHASE, THE DRUG BECOMES A SOLUTION SO THAT IT CAN CROSS THE BIOLOGIC MEMBRANE.
PHARMACEUTIC PHASE
WHEN A DRUG IS GIVEN (subQ), (IM), OR (IV) THERE IS NO _____________________ PHASE.
PHARMACEUTIC
DISSOLUTION PHASE; FIRST PHASE OF DRUG ACTION
PHARMACEUTIC PHASE
DRUGS NEED TO BE IN SOLUTION SO THEY CAN BE ABSORBED IN THE?
GI TRACT
DEFINE DISSOLUTION
THE PROCESS WHERE A DRUG IN SOLID FORM (TABLET OR CAPSULE) MUST DISINTEGRATE INTO SMALL PARTICLES TO DISSOLVE INTO A LIQUID
DEFINE EXCIPIENTS
FILLERS AND INERT SUBSTANCES THAT ARE USED IN DRUG PREPARATION TO ALLOW THE DRUG TO TAKE ON A PARTICULAR SIZE AND SHAPE AND TO ENHANCE DRUG DISSOLUTION.
ARE PUT IN DRUGS TO INCREASE THE ABSORBABILITY OF THE DRUG.
ADDITIVE
(K) ION POTASSIUM AND (NA) SODIUM IN PENICILLIN POTASSIUM AND PENICILLIN SODIUM IS A ADDITIVE BECAUSE?
PENICILLIN IS POORLY ABSORBED IN THE GI TRACT BECAUSE OF GASTRIC ACID, HOWEVER BY MAKING THE DRUG A POTASSIUM OR SODIUM SALT, PENICILLIN CAN THEN BE ABSORBED.
BECAUSE INFANTS HAVE A HIGHER pH (ALKALINE) THAN THOSE OF AN ADULT, INFANTS CAN?
ABSORB MORE PENICILLIN (OR ANY DRUG) THIS IS WHY WE ARE ALWAYS CAREFUL AND DOUBLE CHECK WHEN GIVING ANY MEDICATION TO AN INFANT)
BREAKDOWN OF A TABLET INTO SMALLER PARTICLES
DISINTEGRATION
THE DISSOLVING OF THE SMALLER PARTICLES IN THE GI FLUID BEFORE ABSORPTION IS KNOWN AS?
DISSOLUTION
THE TIME IT TAKES THE DRUG TO DISINTEGRATE AND DISSOLVE TO BECOME AVAILABLE FOR THE BODY TO ABSORB IT
RATE LIMITING
DRUGS ARE BOTH DISINTEGRATED AND ABSORBED FASTER IN ___________________ RATHER THAN ______________.
ACIDIC FLUIDS WITH A pH OF 1 OR 2 RATHER THAN IN ALKALINE FLUIDS. BOTH THE YOUNG AND OLDER ADULTS HAVE LESS GASTRIC ACIDITY; SO DRUG ABSORPTION IS SLOWER FOR THOSE DRUGS ABSORBED PRIMARILY IN THE STOMACH.
ENTERIC-COATED DRUGS:
1. RESIST DISINTEGRATION IN GASTRIC ACID OF STOMACH SO DISINTEGRATION DOES NOT OCCUR TILL IT REACHES THE ALKALINE ENVIRONMENT OF THE SMALL INTESTINE.
2. CAN REMAIN IN STOMACH FOR A LONG TIME SO EFFECT IS DELAYED IN ONSET.
YOU SHOULD NOT __________ ENTERIC-COATED TABLETS, CAPSULES, AND SUSTAINED-RELEASE (BEADED) CAPSULES BECAUSE?
CRUSH; IT WOULD ALTER THE PLACE AND TIME OS ABSORPTION OF THE DRUG.
THE ________ MAY INTERFERE WITH THE DISSOLUTION AND ABSORPTION OF CERTAIN DRUGS. HOWEVER _________ CAN ALSO ENHANCE ABSORPTION OF CERTAIN DRUGS SO SOME SHOULD BE TAKEN WITH IT.
GI TRACT; FOOD
SOME DRUGS IRRITATE THE ___________ ____________, SO FLUIDS OR FOOD MAY BE NECESSARY TO DILUTE THE DRUG CONCENTRATION AND TO ACT AS _______________.
GASTRIC MUCOSA; PROTECTANTS
THE PROCESS OF DRUG MOVEMENT TO ACHIEVE DRUG ACTION
PHARMACOKINETIC PHASE
THE FOUR PROCESSES OF THE PHARMACOKINETIC PHASE ARE:
ABSORPTION, DISTRIBUTION, METABOLISM (BIOTRANSFORMATION) AND EXCRETION (ELIMINATION)
NURSE APPLIES KNOWLEDGE IN THE PHARMACOKINETIC PHASE BY?
ASSESSING CLIENT FOR ADVERSE DRUG EFFECTS, COMMUNICATING ASSESSMENT FINDINGS TO MEMBERS OF THE HEALTH CARE TEAM IN A TIMELY MANNER TO PROMOTE SAFE AND EFFECTIVE DRUG THERAPY FOR THE CLIENT.
ABSORPTION IS
THE MOVEMENT OF DRUG PARTICLES FROM THE GI TRACT TO BOSY FLUIDS BY PASSIVE ABSORPTION, ACTIVE ABSORPTION, OR PINOCYTOSIS.
MOST ORAL DRUGS ARE ABSORBED INTO THE __________ __________ OF THE ___________ ___________ THROUGH THE ACTION OF THE EXTENSIVE _______ ________.
SURFACE AREA; SMALL INTESTINE; MUCOSAL VILLI
ABSORPTION IS ___________ IF THE VILLI ARE ______________ IN NUMBER BECAUSE OF DISEASE, DRUG EFFECT, OR THE REMOVAL OF THE SMALL INTESTINE.
REDUCED; DECREASED
PROTEIN-BASED DRUGS SUCH AS INSULIN AND GROWTH HORMONE ARE ?
DESTROYED IN THE SMALL INTESTINE BY DIGESTIVE ENZYMES
OCCURS MOSTLY BY DIFFUSION (MOVEMENT FROM HIGHER CONCENTRATION TO LOWER CONCENTRATION). WHICH THIS PROCESS, THE DRUG DOES NOT REQUIRE ENERGY TO MOVE ACROSS THE MEMBRANE.
PASSIVE ABSORPTION
REQUIRES A CARRIER SUCH AS AN ENZYME OR PROTEIN TO MOVE THE DRUG AGAINST A CONCENTRATION GRADIENT.. ENERGY IS REQUIRED HERE.
ACTIVE ABSORPTION
A PROCESS BY WHICH CELLS CARRY A DRUG ACROSS THEIR MEMBRANE BY ENGULFING THE DRUG PARTICLES
PINOCYTOSIS
GI MEMBRANE IS COMPOSED MOSTLY OF
LIPID (FAT) AND PROTEIN
LIPID SOLUBLE DRUGS
PASS RAPIDLY THROUGH THE GI MEMBRANE; DRUGS THAT ARE LIPID SOLUBLE AND NONIONIZED ARE ABSORBED FASTER THAN WATER-SOLUBLE AND IONIZED DRUGS.
WATER SOLUBLE DRUGS
NEED A CARRIER, EITHER ENZYME OR PROTEIN, TO PASS THROUGH THE GI MEMBRANE
DIFFERENT TYPES OF DRUGS AND HOW THEY PASS
LARGE PARTICLES PASS THROUGH CELL MEMBRANE IF THEY ARE NON IONIZED.
WEAK ACID DRUGS PASS THROUGH THE STOMACH LINING EASILY AND RAPIDLY.
CALCIUM CARBONATE AND ANTIFUNGALS NEED ACIDIC ENVIRONMENT TO ACHIEVE GRATER DRUG ABSORPTION.
FOOD CAN STIMULATE THE PRODUCTION OF GASTRIC ACIDS.
HYDROCHLORIC ACID DESTROYS SOME DRUGS THEREFORE LARGE DOSES ARE NEEDED TO OFFSET THE DRUG LOST.
DRUGS ADMINISTERED BY DIFFERENT ROUTES DO NOT PASS THROUGH GI TRACT OR LIVER THESES INCLUDE
PARENTERAL DRUGS, EYEDROPS, EARDROPS, NASAL SPRAYS, RESPIRATORY INHALANTS, TRANSDERMAL DRUGS, AND SUBLINGUAL DRUGS.
THINGS THAT AFFECT DRUG EFFECT.
BLOOD FLOW, PAIN, STRESS, HUNGER, FASTING, FOOD, AND pH
DRUGS GIVEN (IM) ARE ABSORBED
FASTER IN MUSCLES THAT HAVE MORE BLOOD VESSELS
SUBQ TISSUE HAVE
FEWER BLOOD VESSELS SO ABSORPTION IS SLOWER IN SUCH TISSUE.
THE PROCESS IN WHICH THE DRUG PASSES TO THE LIVER FIRST IS CALLED
THE FIRST-PASS EFFECT OR HEPATIC FIRST PASS
DRUGS IN THE LIVER
PASS FROM THE INTESTINAL LUMEN TO THE LIVER VIA THE PORTAL VEIN.
IN THE LIVER, DRUGS MAY METABOLIZE TO AN INACTIVE FORM THAT MAY THEN BE EXCRETED, REDUCING AMOUNT OF ACTIVE DRUG. SOME DRUGS GET METABOLIZED AND SOME DONT, IF IT DOES IT CAN ACTIVATE MORE OF THE ORIGINAL DRUG.
BIOAVAILABILITY
PERCENTAGE OF THE ADMINISTERED DRUG DOSE THAT REACHES THE SYSTEMIC CIRCULATION.
ORAL ROUTE: OCCURS AFTER ABSORPTION AND HEPATIC DRUG METABOLISM, ALWAYS LESS THAN 100%. HAVE A HIGH FIRST PASS HEPATIC METABOLISM HAVE HAVE A BIOAVAILABILITY OF ONLY 20% - 40%.
(IV): USUALLY 100%
TO GET THE DESIRED DRUG EFFECT, ORAL DOSE CAN BE 3 TO 5 TIMES LARGER THEN THE DRUG DOSE GIVEN IV.
5 FACTERS THAT ALTER BIOAVAILABILITY
1. THE DRUG FORM
2. ROUTE OF ADMINISTRATION
3. GI MUCOSE AND MOTILITY
4. FOODS AND OTHER DRUGS
5. CHANGES IN LIVER METABOLISM CAUSED BY LIVER DYSFUNCTION OR INADEQUATE HEPATIC BLOOD FLOW
PROCESS WHERE DRUG BECOMES AVAILABLE TO BUDY FLUIDS AND BODY TISSUES
DISTRIBUTION
DISTRIBUTION FACTS
IS INFLUENCED BY BLOOD FLOW, DRUGS AFFINITY TO THE TISSUE, AND PROTEIN-BINDING EFFECT.
VOLUME OF DRUG DISTRIBUTION (Vd) IS DEPENDENT ON?
DRUG DOSE AND ITS CONCENTRATION IN THE BODY. DRUGS WITH A LARGER VOLUME OF DRUG DISTRIBUTION HAVE A LONGER HALF-LIFE AND STAY IN THE BODY LONGER.
HIGHLY-PROTEIN DRUGS
GREATER THEN 89% BOUND TO PROTEINS
MODERATELY HIGHLY-PROTEIN DRUGS
61% TO 89% BOUND TO PROTEINS
MODERATELY PROTEIN DRUGS
30% TO 60% BOUND TO PROTEINS
LOW PROTEIN-BOUND DRUGS
LESS THEN 30%
PORTION OF DRUG THAT IS BOUND IS __________ BECAUSE IT IS NOT AVAILABLE TO RECEPTORS, AND PORTION THAT REMAINS UNBOUND IS __________.
INACTIVE; FREE
FREE DRUGS
DRUGS NOT BOUND TO A PROTEIN.
ARE ACTIVE AND CAUSE A PHARMACOLOGIC RESPONSE. AS FREE DRUG IN CIRCULATION DECREASES, MORE BOUND DRUG IS RELEASED FROM THE PROTEIN TO MAINTAIN THE BALANCE FO FREE DRUG.
CHECKING THE PROTEIN BINDING PERCENTAGE OF ALL DRUGS ADMINISTERED TO A CLIENT IS IMPORTANT TO
AVOID POSSIBLE DRUG TOXICITY
METABOLISM
LIVER IS THE PRIMARY SITE.
DRUGS CAN BE METABOLIZED IN GI TRACT AND LIVER.
MOST DRUGS ARE INACTIVATED BY LIVER ENZYMES, ARE CONVERTED OR TRANSFORMED BY HEPATIC ENZYMES TO INACTIVE METABOLITES OR WATER-SOLUBLE SUBSTANCES FOR EXCRETION.
LARGE % OF DRUGS ARE LIPID SOLUBLE, SO LIVER METABOLIZES THE LIPID-SOLUBLE DRUG SUBSTANCE TO A WATER SOLUBLE SUBSTANCE FOR RENAL EXCRETION. BUT SOME DRUGS ARE TRANSFORMED INTO ACTIVE METABOLISMS CAUSING INCREASED PHARMACOLOGIC RESPONSE.
WHEN DRUG METABOLISM RATE IS DECREASED, EXCESS DRUG ACCUMULATION CAN OCCUR LEADING TO TOXICITY.
THE TIME IT TAKES FOR ONE HALD OF THE DRUG CONCENTRATION TO BE ELIMINATED IS CALLED? AND WHAT AFFECTS IT?
HALF-LIFE (t 1/2).
METABOLISM AND ELIMINATION
DRUG HALF-LIFE (t 1/2)
DRUGS GO THROUGH SEVERAL HALF LIVES BEFORE MORE THAN 90% IS ELIMINATED.
A SHORT HALF LIFE IS CONSIDERED TO BE 4 TO 8 HOURS.
A LONG HALF LIFE IS CONSIDERED TO BE 24 HOURS OR LONGER.
ROUTES OF DRUG ELIMINATION
MAIN ROUTE IS THROUGH THE KIDNEYS (URINE).
OTHERS ARE BILE, FECES, LUNGS, SALIVA, SWEAT, AND BREAST MILK.
KIDNEYS (URINE) ELIMINATION AND FACTS
PROTEIN BOUND DRUGS CANNOT BE FILTERED THROUGH THE KIDNEYS, ONCE DRUG IS RELEASED FROM PROTEIN IT IS A FREE DRUG, AND EVENTUALLY IS EXCRETED IN THE URINE.
URINE pH INFLUENCES DRUG EXCRETION: pH VARIES FROM 4.8 TO 8. ACIDIC URINE PROMOTES ELIMINATION OF WEAK BASE DRUGS, AND ALKALINE URINE PROMOTES ELIMINATION OF WEAK ACID DRUGS.
KIDNEY DISEASE - DECREASES GLOMERULAR FILTRATION RATE (GFR) OR DECREASED RENAL TUBULAR SECRETION, DRUG EXCRETION IS SLOWED OR IMPAIRED.
A DECREASE IN BLOOD FLOW TO KIDNEYS CAN ALSO ALTER DRUG ELIMINATION.
CREATINE CLEARANCE (CLcr)
MOST ACCURATE TEST TO DETERMINE RENAL FUNCTION.
*CREATINE IS A METABOLIC BY-PRODUCT OF MUSCLE THAT IS EXCRETED BY THE KIDNEYS. CLcR TEST COMPARES THE LEVEL OF CREATINE IN THE URINE WITH THE LEVEL OF CREATINE IN THE BLOOD.
VARIES WITH AGE AND GENDER. OLDER ADULTS AND FEMALES HAVE LOWER VALUES BECAUSE OF DECREASED MUSCLE MASS.
A DECREASE IN RENAL GFR RESULTS IN AN INCREASE IN SERUM CREATINE LEVEL AND A DECREASE IN URINE CREATINE CLEARANCE.
**WITH RENAL DYSFUNCTION DRUG DOSAGES NEED TO BE DECREASED, CLcr NEEDS TO BE DETERMINED TO DETERMINE THE RIGHT DOSE. CLcr TEST CONSISTS OF A 12 OR 24 HOUR URINE COLLECTION AND A BLOOD SAMPLE. NORMAL LEVELS ARE 85 TO 135 mL/MIN
THE STUDY OF DRUG-CONCENTRATION AND ITS EFFECTS ON THE BODY IS CALLED?
PHARMACODYNAMICS
DRUG RESPONSE CAN CAUSE A _________ OR _______________ PHYSIOLOGIC EFFECT OR BOTH.
PRIMARY; SECONDARY
THE PRIMARY EFFECT IS ____________, AND THE SECONDARY EFFECT MAY BE ______________ OR ______________.
DESIRABLE; DESIRABLE OR UNDESIRABLE
THE RELATIONSHIP BETWEEN THE MINIMAL VERSUS THE MAXIMAL AMOUNT OF DRUG DOSE NEEDED TO PRODUCE THE DESIRED DRUG RESPONSE IS?
DOSE RESPONSE;
*THE DRUG DOSE IS USUALLY GRADED TO ACHIEVE THE DESIRED DRUG RESPONSE.
ALL DRUGS HAVE A _____________ ____________ EFFECT.
MAXIMUM DRUG (MAXIMAL EFFICACY)
3 IMPORTANT ASPECTS OF PHARMACODYNAMICS ARE?
KNOWING THE DRUGS ONSET, PEAK AND DURATION OF ACTION.
THE TIME IT TAKES TO REACH THE MINIMUM EFFECTIVE CONCENTRATION (MEC) AFTER A DRUG IS ADMINISTERED IS?
ONSET OF ACTION
OCCURS WHEN THE DRUG REACHES ITS HIGHEST BLOOD OR PLASMA CONCENTRATION?
PEAK ACTION
THE LENGTH OF TIME THE DRUG HAS A PHARMACOLOGIC EFFECT IS?
DURATION OF ACTION
SOME DRUGS PRODUCE EFFECTS IN MINUTES BUT OTHERS MAY TAKE HOURS OR DAYS. A "TIME-RESPONSE CURVE" EVALUATES THREE PARAMETERS OF DRUG ACTION: THEY ARE?
ONSET OF DRUG ACTION, PEAK ACTION, AND DURATION OF ACTION.
*IT IS NECESSARY TO UNDERSTAND THE TIME RESPONSE IN RELATIONSHIP TO DRUG ADMINISTRATION. IF DRUG PLASMA OR SERUM LEVEL DECREASES BLEW THRESHOLD OR MEC, ADEQUATE DRUG DOSING IS NOT ACHIEVED; TO HIGH A DRUG LEVEL ABOVE THE MINIMUM TOXIC CONCENTRATION (MTC) CAN RESULT IN TOXICITY.
DRUG-BINDING SITES CAN BE ON PROTEINS, GLYCOPROTEINS, PROTEOLIPIDS AND ENZYMES. THERE ARE 4 RECEPTOR FAMILIES, THEY ARE?
1. KINASE-LINKED RECEPTORS
2. LIGANDGATED ION CHANNELS
3. G PROTEIN-COUPLED RECEPTORS SYSTEMS
4. NUCLEAR RECEPTORS
*DRUGS ACT THROUGH RECEPTORS BY BINDING TO THE RECEPTOR TO PRODUCE (INITIATE) A RESPONSE OR TO BLOCK (PREVENT) A RESPONSE. THE ACTIVITY OF MANY DRUG IS DETERMINED BY THE ABILITY OF THE DRUG TO BIND TO A SPECIFIC RECEPTOR. THE BETTER THE DRUG FITS AT SITE, THE MORE BIOLOGICALLY ACTIVE THE DRUG IS.
THE SITE ON THE RECEPTOR AT WHICH DRUGS BIND
LIGAND-BINDING DOMAIN
KINASE-LINKED RECEPTORS
THE LIGAND-BINDING DOMAIN FOR DRUG BINDING IS ONE THE CELL SURFACE. THE DRUG ACTIVATES THE ENZYME (INSIDE THE CELL), AND A RESPONSE IS INITIATED
LIGAND-GATED ION CHANNELS
THE CHANNEL SPANS THE CELL MEMBRANE AND WITH THIS TYPE OF RECEPTOR, THE CHANNEL OPENS, ALLOWING FOR THE FLOW OF IONS INTO AND OUT OF THE CELL. THE IONS ARE PRIMARILY SODIUM AND CALCIUM.
G PROTEIN-COUPLED RECEPTOR SYSTEMS
THERE ARE THREE COMPONENTS TO THIS RECEPTOR RESPONSE: 1. THE RECEPTOR. 2. THE G PROTEIN THAT BINS WITH GUANOSINE TRIPHOSPHATE (GTP). 3. EFFECTOR THAT IS EITHER AN ENZYME OR AND ION CHANNEL.
NUCLEAR RECEPTORS
FOUND IN CELL NUCLEUS (NOT ON THE SURFACE) OF THE CELL MEMBRANE. ACTIVATION OF RECEPTORS THOUGH THE TRANSCRIPTION FACTORS IS PROLONGED.
*WITH THE FIRST THREE RECEPTORS ACTIVATION OF THE RECEPTORS IS RAPID.
DRUGS THAT PRODUCE A RESPONSE ARE CALLED?
AGONIST
DRUGS THAT BLOCK A RESPONSE ARE CALLED?
ANTOGONIST
*THE EFFECTS OF A ANTOGONIST CAN BE DETERMINED BY THE INHIBITORY (I) ACTION OF THE DRUG CONCENTRATION ON THE RECEPTOR SITE. IC50 IS THE ANTOGONIST DRUG CONCENTRATION REQUIRED TO INHIBIT 50% OF THE MAXIMUM BIOLOGICAL RESPONSE.
DRUGS THAT AFFECT VARIOUS SITES ARE ________ ___________ AND HAVE PROPERTIES OF _____________.
NONSPECIFIC DRUGS; NONSPECIFICITY
*EFFECTS MAT BE EITHER DESIRABLE OR HARMFUL. DRUGS THAT EVOKE A VARIETY OF RESPONSES THROUGHOUT THE BODY HAVE A NONSPECIFIC RESPONSE.
DRUGS MAY ACT AT DIFFERENT RECEPTORS. DRUGS THAT AFFECT VARIOUS RECEPTORS ARE ___________ ___________ OR HAVE PROPERTIES OF _____________.
NONSELECTIVE DRUGS; NONSELECTIVITY
*A VARIETY OF RESPONSES RESULT FROM ACTION AT THESE RECEPTOR SITES. DRUGS THAT PRODUCE A RESPONSE BUT DO NOT ACT ON A RECEPTOR MAY ACT BY STIMULATING OR INHIBITING ENZYME ACTIVITY OR HORMONE PRODUCTION.
FOUR CATEGORIES OF DRUG ACTION ARE? AND FACTS TO KNOW
1. STIMULATION OR DEPRESSION
2. REPLACEMENT
3. INHIBITION OR KILLING OF ORGANISMS
4. IRRITATION
*DRUG ACTION THAT STIMULATES, THE RATE OF CELL ACTIVITY OR THE SECRETION FROM A GLAND INCREASES.
DEPRESSES: CELL ACTIVITY AND FUNCTION OF A SPECIFIC ORGAN ARE REDUCED.
REPLACEMENT: REPLACE ESSENTIAL BODY COMPOUNDS.
INHIBIT OR KILL ORGANISMS: INTERFERE WITH BACTERIAL CELL GROWTH.
IRRITATION: CAN ACT AS MECHANISMS OF IRRITATION (E.G. LAXATIVES IRRITATE THE INNER WALL OF THE COLON)
DRUG ACTION CAN LAST FOR HOURS, DAYS, WEEKS, OR MONTHS DEPENDING ON THE HALF-LIFE OF THE DRUG.
THERAPEUTIC INDEX (TI)
ESTIMATES THE MARGIN OF SAFETY OF THE DRUG THROUGH THE USE OD A RATION THAT MEASURE THE EFFECTIVE (THERAPEUTIC OR CONCENTRATION) DOSE (ED) IN 50% OF PERSONS OR ANIMALS (ED50) AND THE LETHAL DOSE (LD) IN 50% OF ANIMALS (LD50).
*CLOSER THE RATION TO 1, THE GREATER THE DANFER OD TOXICITY*
LD50
TI = ____
ED50
*IN SOME CASES THE ED MAY BE 25% (ED25) OR 75% (ED75).
DRUGS WITH A LOW THERAPEUTIC INDEX
HAVE A NARROW MARGIN OF SAFETY. DRUG DOSE MIGHT NEED ADJUSTMENT, AND PLASMA (SERUM) DRUG LEVELS NEED TO BE MONITORED BECAUSE OF SMALL SAFETY RANGE BETWEEN ED AND LD.
DRUGS WITH A HIGH THERAPEUTIC INDEX
HAVE A WIDE MARGIN OF SAFETY AND LESS DANGER OF PRODUCING TOXIC EFFECTS. PLASMA (SERUM) DRUG LEVELS DO NOT NEED TO BE MONITORED ROUTINELY FOR DRUGS WITH A HIGH TI.
THERAPEUTIC RANGE (THERAPEUTIC WINDOW)
OF A DRUG CONCENTRATION IN PLASMA SHOULD BE BETWEEN THE MINIMUM EFFECTIVE CONCENTRATION IN THE PLASMA FOR OBTAINING DESIRED DRUG ACTION AND THE MINIMUM TOXIC CONCENTRATION (THE TOXIC EFFECT). WHEN THERAPEUTIC RANGE IS GIVEN, IT INCLUDES BOTH PROTEIN-BOUND AND UNBOUND PORTIONS OF THE DRUG.
THE HIGHEST PLASMA CONCENTRATION OF DRUG AT A SPECIFIC TIME IS ?
PEAK DRUG LEVEL;
PEAK DRUG LEVEL INDICATES THE RATE OF ABSORPTION.
ORAL: MIGHT BE 1 TO 3 HOURS
IV: MIGHT BE 10 MINUTES
THE LOWEST PLASMA CONCENTRATION OF A DRUG, AND IT MEASURES THE RATE AT WHICH THE DRUG IS ELIMINATED IS?
TROUGH DRUG LEVEL;
TROUGH LEVELS ARE TAKEN IMMEDIATELY BEFORE TH ENEXT DOSE OF A DRUG.
PEAK AND TROUGH FACTS
PEAK LEVEL INDICATES RATE OF ABSORPTION AND TROUGH LEVEL INDICATES THE RATE OF ELIMINATION OF THE DRUG.
IF EITHER PEAK OR TROUGH LEVELS ARE TOO HIGH TOXICITY CAN OCCUR, IF TO LOW NO THERAPEUTIC EFFECT IS ACHIEVED.
WHEN IMMEDIATE DRUG RESPONSE IS DESIRED, A LARGE INITIAL DOSE, KNOWN AS THE ___________ ___________, OF DRUG IS GIVEN TO ACHIEVE A RAPID MINIMUM EFFECTIVE CONCENTRATION IN THE PLASMA.
LOADING DOSE;
AFTER THE LARGE INITIAL DOSE, A PRESCRIBED DOSAGE PER DAY IS ORDERED.
PHYSIOLOGIC EFFECTS NOT RELATED TO DESIRED DRUG EFFECTS ARE ?
SIDE EFFECTS;
ALL DRUGS HAVE SIDE EFFECTS, DESIRABLE OR NONDESIRABLE.
SIDE EFFECTS RESULT MOSTLY FROM DRUGS THAT LACK SPECIFICITY.
SIDE EFFECTS ARE EXPECTED AS PART OF DRUG THERAPY. THE OCCURRENCE OF THESE EXPECTED BUT UNDESIRABLE SIDE EFFECTS IS NOT A REASON TO DISCONTINUE THERAPY. CAN BE MANAGED WITH DOSAGE ADJUSTMENTS, CHANGING TO A DIFFERENT DRUG IN THE SAME CLASS, OR IMPLEMENTING OTHER INTERVENTIONS.
ARE MORE SEVERE THEN SIDE EFFECTS
ADVERSE REACTIONS;
A RANGE OF UNTOWARD EFFECTS (UNINTENDED AND OCCURRING AT NORMAL DOSES) OF DRUGS THAT CAUSE MILD TO SEVERE SIDE EFFECTS, INCLUDING ANAPHYLAXIS (CARDIOVASCULAR COLLAPSE).
* ADVERSE REACTIONS ARE ALWAYS UNDESIRABLE
THEY MUST ALWAYS BE REPORTED AND DOCUMENTED BECAUSE THEY REPRESENT VARIANCES FROM PLANNED THERAPY.
_______ ________, OR ___________M OF A DRUG CAN BE IDENTIFIED BY MONITORING THE PLASMA (SERUM) THERAPEUTIC RANGE OF THE DRUG.
TOXIC EFFECT, TOXICITY
WHEN THE DRUG LEVEL EXCEEDS THE THERAPEUTIC RANGE, TOXIC EFFECTS ARE LIKELY TO OCCUR FROM OVERDOSING OR DRUG ACCUMULATION.
THE SCIENTIFIC DISCIPLINE STUDYING HOW THE EFFECT OF A DRUG ACTION VARIES FROM A PREDICTED DRUG RESPONSE BECAUSE OF GENETIC FACTORS OR HEREDITY INFLUENCE IS?
PHARMACOGENETICS;
BECAUSE OF DIFFERENT GENETIC MAKEUP, WE DO NOT ALWAYS RESPOND IDENTICALLY TO A DRUG DOSAGE OR PLANNED DRUG THERAPY. GENETIC FACTORS CAN ALTER THE METABOLISM OF THE DRUG IN CONVERTING ITS CHEMICAL FORM TO AN INERT METABOLITE THE DRUG ACTION CAN BE ENHANCED OR DIMINISHED.
REFERS TO A DECREASED RESPONSIVENESS OVER THE COURSE OF THERAPY
TOLERANCE
REFERS TO A RAPID DECREASE IN RESPONSE TO THE DRUG.
TACHYPHYLAXIS;
IS AN ACUTE TOLERANCE,
*IN THE NURSE DOES NOT RECOGNIZE THE DEVELOPMENT OF THE TOLERANCE, THE CLIENT REQUEST FOR MORE PAIN MEDICATION MIGHT BE INTERPRETED AS DRUG SEEKING BEHAVIOR ASSOCIATED WITH ADDICTION.
A PSYCHOLOGICAL BENEFIT FROM A COMPOUND THAT MAY NOT HAVE THE CHEMICAL STRUCTURE OF A DRUG EFFECT IS?
PLACEBO EFFECT;
EFFECTIVE TO 1/3 OF PEOPLE.
THE NURSE CAN INCREASE THE THERAPEUTIC EFFECT OF THE DRUG BUT VIOLATE THE TRUTH-TELLING ETHICAL PRINCIPLE OF A NON THERAPEUTIC DRUG IS PRESENTED AS THERAPEUTIC AGENT.
DRUG ADMINISTRATION
DRUG FORM
ROUTE OF DRUG ADMINISTRATION
MULTIPLE DRUG THERAPY
DRUG INTERACTIONS
DRUG : CLINICAL FACTORS
AGE AND WEIGHT
PRESENT HEALTH DISORDER
OTHER DISEASE ENTITIES
CLIENT DRUG COMPLIANCE
DRUG PHARMACOKINETICS
ABSORPTION
DISTRIBUTION (PB)
METABOLISM (T1/2)
EXCRETION
DRUG PHARMACODYNAMICS
ONSET, PEAK, AND DURATION
THERAPEUTIC RANGE (THERAPEUTIC WINDOW)
SIDE EFFECTS, ADVERSE REACTIONS