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© Paradigm Publishing, Inc. 2
Learning Objectives
• Identify the major types of antibiotics by drug class.
• Know which auxiliary labels to use when dispensing major types of antibiotics.
• Define therapeutic effects side effects, and administration routes of major antibiotics.
• Use antibiotic and general drug terminology correctly in written and oral communication.
3© Paradigm Publishing, Inc.
Fighting Bacterial Infections
• Bacteria– Single-celled organisms occurring in
most environments
• Infection– Condition in which bacteria grow in body
tissues and cause tissue damage by their presence or by toxins they produce
4© Paradigm Publishing, Inc.
Types of Bacteria
• Aerobic– Needs oxygen to survive
• Anaerobic– Survives in the absence of oxygen
5© Paradigm Publishing, Inc.
Bacteria Shapes
(a) Round cocci
(b) Rod-like bacilli
(c) Spiral-shaped spirochetes
6© Paradigm Publishing, Inc.
Gram Stain
(a) Gram-positive bacteria turn purple
(b) Gram-negative bacteria appear red
7© Paradigm Publishing, Inc.
Gram Stain Results and Related Diseases
Shape Gram Stain Bacteria Related Disease
rods gram-positive
Corynebacteria endocarditis
rods gram-negative
E. Coli UTI
8© Paradigm Publishing, Inc.
Gram Stain Results and Related Diseases
Shape Gram Stain Bacteria Related Disease
cocci gram-positive
Staphylococcus toxic shock syndrome
cocci gram-negative
Neisseria gonorrhea
9© Paradigm Publishing, Inc.
Gram Stain Results and Related Diseases
Shape Gram Stain
Bacteria Related Disease
curved or spiral rods
gram-negative
Campylobacter septicemia
spirochetes gram-negative
Treponema palladium
syphilis
10© Paradigm Publishing, Inc.
How Antibiotics Work
• Prevent folic acid synthesis– Sulfonamides
• Inhibit cell wall formation– Penicillins– Cephalosporins
11© Paradigm Publishing, Inc.
How Antibiotics Work• Prevent folic acid synthesis• Inhibit cell wall formation
• Block protein formation– Macrolides
– Tetracyclines
– Aminoglycosides
• Interfere with DNA formation
12© Paradigm Publishing, Inc.
How Antibiotics Work• Prevent folic acid synthesis• Inhibit cell wall formation• Block protein formation• Interfere with DNA formation
• Disrupt cell membranes– Cyclic lipopeptides
• Disrupt DNA structure– Metronidazole
13© Paradigm Publishing, Inc.
Dispensing Issues of Antibiotics
• Mix exactly as directed by manufacturer
• Swab counting tray with alcohol between drugs to prevent cross-contamination
Warning!
14© Paradigm Publishing, Inc.
Side Effects of Antibiotics
• Most antibiotics taken on an empty stomach to attain faster absorption
• Exceptions– nitrofurantoin (Macrobid, Macrodantin)– cefuroxime (Ceftin, Zinacef)
15© Paradigm Publishing, Inc.
Antimicrobial Resistance
• Developing largely because of
– Overuse
– Misuse
• Superinfection may occur
16© Paradigm Publishing, Inc.
Antimicrobial Resistance
• Pharmacy technician—place a label on antibiotics advising patient to take all of the medication
© Paradigm Publishing, Inc. 18
Terms to Remember
bactericidal agent
bacteriostatic agent
superinfection
Major classes of antibiotic drugs
• Sulfonamides
• Pencillins
• Cephalosporins
• Tetracyclines and Tigecycline
• Macrolides
• Ketolides
• Quinolones
• Streptogramins
• Aminoglycosides
• Cyclic Lipopetides
19© Paradigm Publishing, Inc.
20© Paradigm Publishing, Inc.
Sulfonamides
• AKA “sulfa drugs”
• Effective against a broad range of microorganisms
• Block specific step in biosynthetic pathway of folic acid
• Interfere with PABA and folic acid formation, thereby destroying bacteria
© Paradigm Publishing, Inc. 21
Drug ListSulfonamides
– sulfamethoxazole-trimethoprim (Bactrim, Bactrim DS, Cotrim, Cotrim DS, Septra, Septra DS)
– sulfasalazine (Azulfidine)
– sulfisoxazole (Gantrisin)
– Related drug: nitrofurantoin (Macrobid, Macrodantin)
22© Paradigm Publishing, Inc.
Allergy to Sulfonamides
• If patient is allergic to sulfa, then drug of choice is nitrofurantoin (Macrobid, Macrodantin)
23© Paradigm Publishing, Inc.
Therapeutic Uses of Sulfonamides
• Urinary tract infections (UTIs)
• Otitis media
• Ulcerative colitis
• Lower respiratory infections
• Prophylaxis in Pneumocystis carinii pneumonia in immunocompromised
24© Paradigm Publishing, Inc.
Side Effects of Sulfonamides
• Rash
• Nausea
• Drug fever
• Vomiting
• Jaundice
• Kidney damage
• Blood complications
25© Paradigm Publishing, Inc.
Dispensing Issues of Sulfonamides
• Avoid sun
• Maintain adequate fluid intake
26© Paradigm Publishing, Inc.
Penicillins
• Low toxicity• Derivatives created by manipulating basic
molecular structure of drug
• Kills bacteria by preventing them from forming rigid cell wall
• Because human cells do not have rigid cell walls, they are not affected
© Paradigm Publishing, Inc. 27
Drug ListPenicillin Drugs
– amoxicillin (Amoxil)
– ampicillin (Principen)– penicillin G (various brand names,
also different salts, i.e. potassium, sodium)
– penicillin V (Veetids)
© Paradigm Publishing, Inc. 28
Drug ListResistant Penicillins
Penicillinase-Resistant Penicillins– dicloxacillin (Dycil)
– nafcillin (Unipen)– oxacillin (none)
© Paradigm Publishing, Inc. 29
Drug ListResistant Penicillins
Extended-Spectrum Penicillins– carbenicillin (Geocillin)
– piperacillin (none)
– ticarcillin (Ticar)
© Paradigm Publishing, Inc. 30
Drug List
Resistant Penicillins
Penicillin Combinations– amoxicillin-clavulanate
(Augmentin)
– ampicillin-sulbactam (Unasyn)
– piperacillin-tazobactam (Zosyn)
– ticarcillin-clavulanate (Timentin)
31© Paradigm Publishing, Inc.
Therapeutic Uses of Penicillins
• Abscesses
• Beta-hemolytic streptococcus
• Meningitis
• Otitis media
• Pneumonia
32© Paradigm Publishing, Inc.
Therapeutic Uses of Penicillins
• Respiratory infections
• Strep throat
• Tooth and gum infections
• Sexually transmitted diseases (STDs; syphilis and gonorrhea)
• Endocarditis due to streptococci
33© Paradigm Publishing, Inc.
Side Effects of Penicillins
• Diarrhea
• Allergies in 7% to 10% of population
34© Paradigm Publishing, Inc.
Dispensing Issues of Penicillins
• Take on an empty stomach – Food slows absorption
– Acids in fruit juices or colas could deactivate drug
35© Paradigm Publishing, Inc.
Resistance to Penicillins
• Penicillinase-resistant penicillins work against gram-positive aerobes
• Extended-spectrum penicillins are more resistant to gram-negative bacteria
• Penicillin combinations improve effect
36© Paradigm Publishing, Inc.
Cephalosporins
• Mechanism of action similar to penicillins
• Person allergic to penicillin has about 1% chance of being allergic to cephalosporins
© Paradigm Publishing, Inc. 37
Drug ListFirst-Generation Cephalosporins
– cefadroxil (Duricef)
– cefazolin (Ancef)
– cephalexin (Keflex)
© Paradigm Publishing, Inc. 38
Drug ListSecond-Generation Cephalosporins
– cefaclor (Ceclor)
– cefprozil (Cefzil)
– cefuroxime (Ceftin, Zinacef)
© Paradigm Publishing, Inc. 39
Drug ListThird-Generation Cephalosporins
– cefdinir (Omnicef)
– cefditoren (Spectracef)
– cefixime (Suprax)
– cefotaxime (Claforan)
– cefpodoxime (Vantin)
© Paradigm Publishing, Inc. 40
Drug ListThird-Generation Cephalosporins
– ceftazidime (Fortaz)
– ceftibuten (Cedax)
– ceftizoxime (Cefizox)
– ceftriaxone (Rocephin)
42© Paradigm Publishing, Inc.
Dispensing Issues of Cephalosporins
• Alert pharmacist if patient who is allergic to penicillin is receiving a cephalosporin Rx
• If patient wants cephalosporin dispensed, document communication in case of cross-reaction
Warning!
43© Paradigm Publishing, Inc.
First-Generation Cephalosporins
• Similar to penicillinase-resistant penicillins but have greater gram-negative coverage
• Used for – Community-acquired infections– Mild to moderate infections
44© Paradigm Publishing, Inc.
Second-Generation Cephalosporins
• Increased activity, especially against Haemophilus influenzae
• Used for – Otitis media in children– Respiratory infections– Urinary tract infections (UTIs)
45© Paradigm Publishing, Inc.
Third-Generation Cephalosporins
• Active against wide spectrum of gram-negative organisms
• Long half-life, so once-a-day dosing for some
• Used for– Ambulatory patients– Children (dosing before or after school)
46© Paradigm Publishing, Inc.
Fourth-Generation Cephalosporins
• Broad-spectrum coverage, such as cefepime (Maxipime)
• Used for– Pneumonia– UTIs– Sepsis
• IV form mixed in NS or D5W
47© Paradigm Publishing, Inc.
Side Effects of Cephalosporins
• Share side effects of penicillin
• A few may initiate unique toxic reactions
• Lower frequency of toxicity than many other antibiotics
48© Paradigm Publishing, Inc.
Dispensing Issues of Cephalosporins
• All cephalosporins look alike when written in the generic form
• Watch dosing and indications for use
Warning!
49© Paradigm Publishing, Inc.
Drugs Related to Penicillins and Cephalosporins
• New beta-lactam drugs differ slightly in structure
• Carabpenems, carbacephems, and monobactam
• Some used for serious infections
© Paradigm Publishing, Inc. 50
Drug ListCarbapenems
– ertapenem (Invanz)
– imipenem-cilastatin (Primaxin)
– meropenem (Merrem I.V.)
© Paradigm Publishing, Inc. 51
Drug List
Carbacephem– doripenem (Doribax)
– loracarbef (Lorabid)
Monobactam– aztreonam (Azactam)
52© Paradigm Publishing, Inc.
Tetracyclines
• Broad-spectrum bacteriostatic antibiotics
• Inhibit protein synthesis in bacteria by binding to ribosomes
• Suppress infection, but require phagocytes to eradicate bacteria completely
© Paradigm Publishing, Inc. 53
Drug ListTetracyclines
– demeclocycline (Declomycin)
– doxycycline (Vibramycin, Oracea, Adoxa)
– minocycline (Minocin, Soladyne)
– tetracycline (Sumycin)
54© Paradigm Publishing, Inc.
Therapeutic Uses of Tetracyclines
• Acne• Anthrax• Chronic bronchitis• Lyme disease• Mycoplasma pneumoniae infection• Rickettsia infection• Some sexually transmitted diseases, such
as Chlamydia infection
55© Paradigm Publishing, Inc.
Side Effects of Tetracyclines
• Gastrointestinal upset with nausea and vomiting
56© Paradigm Publishing, Inc.
Dispensing Issues of Tetracyclines
• Avoid antacids to avoid chelation with minerals
• Photosensitization
• Pregnant women and children up to age 9 must avoid
57© Paradigm Publishing, Inc.
Dispensing Issues of Tetracyclines
• Expired drugs can be toxic, can cause fatal renal syndrome
• Pharmacy technician always watch the expiration date
Warning!
58© Paradigm Publishing, Inc.
Dispensing Issues of Tetracyclines
• Government agencies stockpiling tetracyclines due to concern over terrorist attack
• Due to toxicity: must be rotated; destroy when out of date
Warning!
59© Paradigm Publishing, Inc.
Tigecycline
• New drug class: glycylcycline
• Similar to tetracyclines
• Used for– Skin infections– Intra-abdominal infections
61© Paradigm Publishing, Inc.
Macrolides
• Inhibit protein synthesis by combining with ribosomes
• Used primarily to treat pulmonary infections
© Paradigm Publishing, Inc. 62
Drug ListMacrolides
– azithromycin (Zithromax, Z Pak, Zmax)
– clarithromycin (Biaxin)
– dirithromycin (Dynabac)
– erythromycin base (Eryc, Ery-Tab)
© Paradigm Publishing, Inc. 63
Drug ListMacrolides
– erythromycin ethylsuccinate (E.E.S., EryPed)
– erythromycin lactobionate (Erythrocin)
– erythromycin stearate (Erythrocin)
– erythromycin-sulfisoxazole (Pediazole)
64© Paradigm Publishing, Inc.
Therapeutic Uses of Macrolides
Drugs of choice for– Chlamydia– Group A beta-hemolytic streptococcus– H. influenzae– Legionnaires’ disease– M. pneumoniae– S. pneumoniae
65© Paradigm Publishing, Inc.
Dispensing Issues of Macrolides
• Most antibiotics taken on empty stomach
• Some forms of erythromycin can cause severe GI distress and should be taken with food
66© Paradigm Publishing, Inc.
Dispensing Issues of Macrolides
• Can be misread– erythromycin– azithromycin
• Dosing should help identify drug
Warning!
67© Paradigm Publishing, Inc.
Ketolides
• Bind to ribosomal subunits and block protein synthesis
• May inhibit newly forming ribosomes
• Bacteria resistant to macrolides, lincomycin derivatives, and streptogramins is also resistant to ketolides
• Used to treat bacterial infections in lungs and sinuses
69© Paradigm Publishing, Inc.
Quinolones
• Strong, rapid bactericidal action against– Most gram-negative bacteria– Many gram-positive bacteria
• Antagonize enzyme responsible for coiling and replicating DNA, causing DNA breakage and cell death
© Paradigm Publishing, Inc. 70
Drug ListQuinolones
– ciprofloxacin (Cipro)
– gatifloxacin (Tequin)
– gemifloxacin (Factive)
– levofloxacin (Levaquin)
– moxifloxacin (Avelox)
– norfloxacin (Noroxin)
– ofloxacin (Floxin)
71© Paradigm Publishing, Inc.
Therapeutic Uses of Quinolones
• Bone and joint infections caused by gram-negative organisms
• Infectious diarrhea• Ophthalmic infections• Some sexually transmitted diseases• Upper respiratory infections• Urinary tract infections (UTIs)
72© Paradigm Publishing, Inc.
Side Effects of Quinolones
• Primarily gastrointestinal, with nausea and vomiting
• Some joint swelling, dizziness, and unpleasant taste
• Can cause joint problems and malformations
• Patients have tendency to injure tendons
73© Paradigm Publishing, Inc.
Dispensing Issues of Quinolones
• Not to be given with theophylline
• Antacids interfere with absorption
• Avoid sun
74© Paradigm Publishing, Inc.
Streptogramins
• Inhibit protein synthesis within the bacterial ribosomes
• Alternative to vancomycin
• Side effects similar to quinolones: nausea, vomiting, joint swelling, dizziness
76© Paradigm Publishing, Inc.
Aminoglycosides
• Used to treat serious infections
• Inhibits bacterial protein synthesis by binding to ribosomal subunits
• After first dose, dosage adjusted according to plasma concentrations
© Paradigm Publishing, Inc. 77
Drug ListAminoglycosides
– amikacin (Amikin)– gentamicin (Garamycin)– kanamycin (Kantrex)– neomycin (Mycifradin, Neo-Fradin,
Neo Rx)– streptomycin (none)– tobramycin (Nebcin)
78© Paradigm Publishing, Inc.
Side Effects of Aminoglycosides
• Nephrotoxicity (destructive to kidney)
• Ototoxicity (damage organs of hearing)– Equilibrium problems – Tinnitus– Permanent deafness
• Neuromuscular blockade
79© Paradigm Publishing, Inc.
Dosing of Aminoglycosides
• Dosed 1x/daily instead of 2 to 3x/daily
• Less frequent dosing may reduce toxicity– Less drug accumulates in kidneys and ears
– Simplifies drug monitoring
• Trough levels should be checked before second dose to confirm drug elimination
80© Paradigm Publishing, Inc.
Cyclic Lipopetides
• Bind bacterial membranes causing cell membrane to depolarize
• Leads to– Inhibition of DNA and RNA synthesis– Bacterial death
© Paradigm Publishing, Inc. 81
Drug List
Cyclic Lipopetides– daptomycin (Cubicin)
• Do not take with statins
Warning!
© Paradigm Publishing, Inc. 82
Terms to Remember
sulfonamides
penicillin
cephalosporin
community-acquired
NS
D5W
© Paradigm Publishing, Inc. 83
Terms to Remember
tetracycline
chelation
macrolide
ketolide
quinolone
streptogramin
© Paradigm Publishing, Inc. 84
Terms to Remember
aminoglycoside
sepsis
nephrotoxicity
ototoxicity
cyclic lipopeptide
hypotension
85© Paradigm Publishing, Inc.
Other Antibiotics
• Five important antibiotics are structurally distinct from– Those in other classes– Each other
© Paradigm Publishing, Inc. 86
Drug ListAntibiotics Independent of Class
– clindamycin (Cleocin)
– linezolid (Zyvox)
– metronidazole (Flagyl)
– pentamidine (NebuPent, Pentam)
– vancomycin (Vancocin)
87© Paradigm Publishing, Inc.
vancomycin (Vancocin)
• Bacterial resistance increasing due to overuse
• Strict CDC guidelines for handling and use
Warning!
88© Paradigm Publishing, Inc.
clindamycin (Cleocin)
• Broad-spectrum antibiotic used for– Acne– Penicillin alternative in dental
prophylaxis– Anaerobic pneumonia– Bone and bowel infections– Female genital and intra-abdominal
infections
89© Paradigm Publishing, Inc.
clindamycin (Cleocin)
• If patient develops diarrhea, drug must be discontinued
Warning!
90© Paradigm Publishing, Inc.
linezolid (Zyvox)
• First oxazolidinone approved by FDA
• Inhibits bacterial protein synthesis
• Drug must be protected from light
91© Paradigm Publishing, Inc.
metronidazole (Flagyl)
• Pharmacy technician—place No Alcohol warning sticker on medication
92© Paradigm Publishing, Inc.
pentamidine (NebuPent, Pentam)
• Second-line agent for Pneumocystis carinii
• Mechanism of action unknown
• Patient may develop sudden hypotension (low blood pressure)
93© Paradigm Publishing, Inc.
Storage of Liquid Antibiotics
• After lyophilized (powdered) antibiotics are mixed– Some need refrigeration– Others stored at room temperature
• Pharmacy technician may tell storage information to patient
94© Paradigm Publishing, Inc.
Ophthalmic Antibiotics
• Some antibiotics have ophthalmic (eye) dosage forms
• Very few antibiotics have otic forms– Very painful in the eye– Otic medicines have different pH than
the eye
© Paradigm Publishing, Inc. 95
Drug ListOphthalmic Dosage Forms
– azithromycin (AzaSite)
– bacitracin (AKtracin)
– ciprofloxacin (Occuflox, Ciprodex)
– erthromycin (Ilotycin)
– gatifloxacin (Zymar)
© Paradigm Publishing, Inc. 96
Drug ListOphthalmic Dosage Forms
– gentamicin (Gentak, Genoptic)
– moxifloxacin (Vigamox)
– oxfloxacin (Ocuflox)
– sodium sulfacetamide (Bleph 10)
– tobramycin (Tobrex)
97© Paradigm Publishing, Inc.
Dispensing Issues of Ophthalmic Antibiotics
• Newer eye drops very expensive, often rejected by insurance companies
• Pharmacy technician will need to let prescriber know– What eye drops are available– Which ones insurance most likely cover
© Paradigm Publishing, Inc. 98
Terms to Remember
ophthalmicto be used in the eye
otic to be used in the ear
pHa measurement of acidity or alkalinity; pH 7 neutral
99© Paradigm Publishing, Inc.
Treating Complications of Infections
• drotrecogin alfa (Xigris)– Not an antibiotic
– Used in treating some complications of sepsis (life-threatening result of serious infections)
– Anticoagulant and anti-inflammatory
– High cost, strict guidelines limit use