1. 1 © Paradigm Publishing, Inc. Chapter 4 Antibiotics

2. © 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. 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. 4 © Paradigm Publishing, Inc. Types of Bacteria Aerobic –Needs oxygen to survive Anaerobic –Survives in the absence of oxygen

5. 5 © Paradigm Publishing, Inc. Bacteria Shapes (a) Round cocci (b) Rod-like bacilli (c) Spiral-shaped spirochetes

6. 6 © Paradigm Publishing, Inc. Gram Stain (a)Gram-positive bacteria turn purple (b)Gram-negative bacteria appear red

7. 7 © Paradigm Publishing, Inc. Gram Stain Results and Related Diseases ShapeGram StainBacteriaRelated Disease rodsgram- positive Corynebacteriaendocarditis rodsgram- negative E. ColiUTI

8. 8 © Paradigm Publishing, Inc. Gram Stain Results and Related Diseases ShapeGram StainBacteriaRelated Disease coccigram- positive Staphylococcustoxic shock syndrome coccigram- negative Neisseriagonorrhea

9. 9 © Paradigm Publishing, Inc. Gram Stain Results and Related Diseases ShapeGram Stain BacteriaRelated Disease curved or spiral rods gram- negative Campylobactersepticemia spirochetesgram- negative Treponema palladium syphilis

10. 10 © Paradigm Publishing, Inc. How Antibiotics Work Prevent folic acid synthesis –Sulfonamides Inhibit cell wall formation –Penicillins –Cephalosporins

11. 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. 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. 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. 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. 15 © Paradigm Publishing, Inc. Antimicrobial Resistance Developing largely because of –Overuse –Misuse Superinfection may occur

16. 16 © Paradigm Publishing, Inc. Antimicrobial Resistance Pharmacy technician—place a label on antibiotics advising patient to take all of the medication

17. © Paradigm Publishing, Inc.17 Terms to Remember bacteria infection aerobic anaerobic Gram staining

18. © Paradigm Publishing, Inc.18 Terms to Remember bactericidal agent bacteriostatic agent superinfection

19. Major classes of antibiotic drugs Sulfonamides Pencillins Cephalosporins Tetracyclines and Tigecycline Macrolides Ketolides Quinolones Streptogramins Aminoglycosides Cyclic Lipopetides 19 © Paradigm Publishing, Inc.

20. 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

21. © Paradigm Publishing, Inc.21 Drug List Sulfonamides –sulfamethoxazole-trimethoprim (Bactrim, Bactrim DS, Cotrim, Cotrim DS, Septra, Septra DS) –sulfasalazine (Azulfidine) –sulfisoxazole (Gantrisin) –Related drug: nitrofurantoin (Macrobid, Macrodantin)

22. 22 © Paradigm Publishing, Inc. Allergy to Sulfonamides If patient is allergic to sulfa, then drug of choice is nitrofurantoin (Macrobid, Macrodantin)

23. 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. 24 © Paradigm Publishing, Inc. Side Effects of Sulfonamides Rash Nausea Drug fever Vomiting Jaundice Kidney damage Blood complications

25. 25 © Paradigm Publishing, Inc. Dispensing Issues of Sulfonamides Avoid sun Maintain adequate fluid intake

26. 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

27. © Paradigm Publishing, Inc.27 Drug List Penicillin Drugs – amoxicillin (Amoxil) – ampicillin (Principen) – penicillin G (various brand names, also different salts, i.e. potassium, sodium) – penicillin V (Veetids)

28. © Paradigm Publishing, Inc.28 Drug List Resistant Penicillins Penicillinase-Resistant Penicillins – dicloxacillin (Dycil) – nafcillin (Unipen) – oxacillin (none)

29. © Paradigm Publishing, Inc.29 Drug List Resistant Penicillins Extended-Spectrum Penicillins – carbenicillin (Geocillin) – piperacillin (none) – ticarcillin (Ticar)

30. © Paradigm Publishing, Inc.30 Drug List Resistant Penicillins Penicillin Combinations –amoxicillin-clavulanate (Augmentin) –ampicillin-sulbactam (Unasyn) – piperacillin-tazobactam (Zosyn) – ticarcillin-clavulanate (Timentin)

31. 31 © Paradigm Publishing, Inc. Therapeutic Uses of Penicillins Abscesses Beta-hemolytic streptococcus Meningitis Otitis media Pneumonia

32. 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. 33 © Paradigm Publishing, Inc. Side Effects of Penicillins Diarrhea Allergies in 7% to 10% of population

34. 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. 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. 36 © Paradigm Publishing, Inc. Cephalosporins Mechanism of action similar to penicillins Person allergic to penicillin has about 1% chance of being allergic to cephalosporins

37. © Paradigm Publishing, Inc.37 Drug List First-Generation Cephalosporins –cefadroxil (Duricef) –cefazolin (Ancef) –cephalexin (Keflex)

38. © Paradigm Publishing, Inc.38 Drug List Second-Generation Cephalosporins –cefaclor (Ceclor) –cefprozil (Cefzil) –cefuroxime (Ceftin, Zinacef)

39. © Paradigm Publishing, Inc.39 Drug List Third-Generation Cephalosporins –cefdinir (Omnicef) –cefditoren (Spectracef) –cefixime (Suprax) –cefotaxime (Claforan) –cefpodoxime (Vantin)

40. © Paradigm Publishing, Inc.40 Drug List Third-Generation Cephalosporins –ceftazidime (Fortaz) –ceftibuten (Cedax) –ceftizoxime (Cefizox) –ceftriaxone (Rocephin)

41. © Paradigm Publishing, Inc.41 Drug List Fourth-Generation Cephalosporins –cefepime (Maxipime)

42. 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. 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. 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. 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. 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 D 5 W

47. 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. 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. 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

50. © Paradigm Publishing, Inc.50 Drug List Carbapenems –ertapenem (Invanz) –imipenem-cilastatin (Primaxin) –meropenem (Merrem I.V.)

51. © Paradigm Publishing, Inc.51 Drug List Carbacephem –doripenem (Doribax) –loracarbef (Lorabid) Monobactam –aztreonam (Azactam)

52. 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

53. © Paradigm Publishing, Inc.53 Drug List Tetracyclines –demeclocycline (Declomycin) –doxycycline (Vibramycin, Oracea, Adoxa) –minocycline (Minocin, Soladyne) –tetracycline (Sumycin)

54. 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. 55 © Paradigm Publishing, Inc. Side Effects of Tetracyclines Gastrointestinal upset with nausea and vomiting

56. 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. 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. 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. 59 © Paradigm Publishing, Inc. Tigecycline New drug class: glycylcycline Similar to tetracyclines Used for –Skin infections –Intra-abdominal infections

60. © Paradigm Publishing, Inc.60 Drug List Tigecycline –tigecycline (Tygacil)

61. 61 © Paradigm Publishing, Inc. Macrolides Inhibit protein synthesis by combining with ribosomes Used primarily to treat pulmonary infections

62. © Paradigm Publishing, Inc.62 Drug List Macrolides –azithromycin (Zithromax, Z Pak, Zmax) –clarithromycin (Biaxin) –dirithromycin (Dynabac) –erythromycin base (Eryc, Ery-Tab)

63. © Paradigm Publishing, Inc.63 Drug List Macrolides –erythromycin ethylsuccinate (E.E.S., EryPed) –erythromycin lactobionate (Erythrocin) –erythromycin stearate (Erythrocin) –erythromycin-sulfisoxazole (Pediazole)

64. 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. 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. 66 © Paradigm Publishing, Inc. Dispensing Issues of Macrolides Can be misread –erythromycin –azithromycin Dosing should help identify drug Warning!

67. 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

68. © Paradigm Publishing, Inc.68 Drug List Ketolides –telithromycin (Ketek)

69. 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

70. © Paradigm Publishing, Inc.70 Drug List Quinolones –ciprofloxacin (Cipro) –gatifloxacin (Tequin) –gemifloxacin (Factive) –levofloxacin (Levaquin) –moxifloxacin (Avelox) –norfloxacin (Noroxin) –ofloxacin (Floxin)

71. 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. 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. 73 © Paradigm Publishing, Inc. Dispensing Issues of Quinolones Not to be given with theophylline Antacids interfere with absorption Avoid sun

74. 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

75. © Paradigm Publishing, Inc.75 Drug List Streptogramins –quinupristin-dalfopristin (Synercid)

76. 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

77. © Paradigm Publishing, Inc.77 Drug List Aminoglycosides –amikacin (Amikin) –gentamicin (Garamycin) –kanamycin (Kantrex) –neomycin (Mycifradin, Neo-Fradin, Neo Rx) –streptomycin (none) –tobramycin (Nebcin)

78. 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. 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. 80 © Paradigm Publishing, Inc. Cyclic Lipopetides Bind bacterial membranes causing cell membrane to depolarize Leads to –Inhibition of DNA and RNA synthesis –Bacterial death

81. © Paradigm Publishing, Inc.81 Drug List Cyclic Lipopetides –daptomycin (Cubicin) Do not take with statins

82. © Paradigm Publishing, Inc.82 Terms to Remember sulfonamides penicillin cephalosporin community-acquired NS D5WD5W

83. © Paradigm Publishing, Inc.83 Terms to Remember tetracycline chelation macrolide ketolide quinolone streptogramin

84. © Paradigm Publishing, Inc.84 Terms to Remember aminoglycoside sepsis nephrotoxicity ototoxicity cyclic lipopeptide hypotension

85. 85 © Paradigm Publishing, Inc. Other Antibiotics Five important antibiotics are structurally distinct from –Those in other classes –Each other

86. © Paradigm Publishing, Inc.86 Drug List Antibiotics Independent of Class –clindamycin (Cleocin) –linezolid (Zyvox) –metronidazole (Flagyl) –pentamidine (NebuPent, Pentam) –vancomycin (Vancocin)

87. 87 © Paradigm Publishing, Inc. vancomycin (Vancocin) Bacterial resistance increasing due to overuse Strict CDC guidelines for handling and use Warning!

88. 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. 89 © Paradigm Publishing, Inc. clindamycin (Cleocin) If patient develops diarrhea, drug must be discontinued Warning!

90. 90 © Paradigm Publishing, Inc. linezolid (Zyvox) First oxazolidinone approved by FDA Inhibits bacterial protein synthesis Drug must be protected from light

91. 91 © Paradigm Publishing, Inc. metronidazole (Flagyl) Pharmacy technician—place No Alcohol warning sticker on medication

92. 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. 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. 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

95. © Paradigm Publishing, Inc.95 Drug List Ophthalmic Dosage Forms –azithromycin (AzaSite) –bacitracin (AKtracin) –ciprofloxacin (Occuflox, Ciprodex) –erthromycin (Ilotycin) –gatifloxacin (Zymar)

96. © Paradigm Publishing, Inc.96 Drug List Ophthalmic Dosage Forms –gentamicin (Gentak, Genoptic) –moxifloxacin (Vigamox) –oxfloxacin (Ocuflox) –sodium sulfacetamide (Bleph 10) –tobramycin (Tobrex)

97. 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

98. © Paradigm Publishing, Inc.98 Terms to Remember ophthalmic to be used in the eye otic to be used in the ear pH a measurement of acidity or alkalinity; pH 7 neutral

99. 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

100. © Paradigm Publishing, Inc.100 Drug List Adjunct in Treating Sepsis –drotrecogin alfa (Xigris)

101. © Paradigm Publishing, Inc.101 Assignments Complete Chapter Review activities Answer questions in Study Notes document Study Partner –Quiz in review mode –Matching activities –Drug tables