ANTIVIRALS & ANTIBACTERIALS

1. ANTIVIRALS & ANTIBACTERIALS Cheryl Davis-Triplett

2. WHAT IS A VIRUS? • Obligate intracellular organism that uses the cell to reproduce. They replicate by using their own RNA or DNA to manipulate the cells they infect • They cause cell death

3. WHAT IS A BACTERIA? • Smallest living cell. They have a cell wall and a cell membrane. They do not have a nucleus. • Bacteria divide by cell division.

4. HOW DO WE FIGHT BACTERIA AND VIRUSES • Antibacterials work with the body’s own defenses to stop the infection process. • Antivirals prevent or delay the speed of viral replication.

5. ANTIBACTERIAL MODE OF ACTION • Inhibit cell wall synthesis. Which Antibiotic class uses this mode? • Penicillins and Cephalosporins • Inhibit protein synthesis. Which Antibiotic class uses this mode? • Tetracyclines, Macrolides, and Aminoglydosides

6. MODE OF ACTION (cont.) • Inhibit nucleic acid synthesis. Which Antibiotic class uses this mode? • Fluoroquinolones • Inhibit folic acid synthesis. Which Antibiotic class uses this mode? • Sulfonamides

7. MODE OF ACTION (cont.) • Alteration in membrane permeability. Which drugs use this mode? • Ampho-TERRIBLE B, Nystatin, Polymyxin, and Colistin

8. ANTIVIRAL MODE OF ACTION • Viruses enter healthy cells and use their deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) to generate more viruses. • The growth cycle of viruses depends on the host cell enzymes and cell substrates for viral replication. • Viruses live and reproduce when they are within living cells.

9. OVERVIEW • Penicillins • Cephalopsporins • Macrolides • Tetracyclines • Aminoglycosides • Fluorquinalones • Sulfonomides • Antivirals • Viral flu treatment (drugs and how/when they are given) • Herpes simplex • Aminoglycosides (SE/ADEs, drug-drug) • Otitis media treatment • Amphotericin B

10. Common factors among Antibiotics • Indications: bacterial infections • SE/AD: superinfections, NVD • Contraindications: hypersensitivity • Interventions: C&S • Pt Teaching: S&S hypersensitivity, finish prescribed dose, medical alert bracelet

11. PENICILLIN Indication for Use • Respiratory tract infection • Urinary tract infection • Otitis media • Sinusitis Example Drug • Amoxicillin(Amoxil)

12. PENICILLIN (cont.) Side Effects • NVD, rash, edema, stomatitis • AR: Super Infections (vaginitis) • Life threatening: Blood dyscrasias, hemolytic anemia, bone marrow depression, respiratory distress Contraindications • Allergy to penicillin • Severe renal disorder

13. PENICILLIN (cont.) Interactions • Drug: asprin, tetracycline, erythromycin. • Lab: AST, ALT, BUN, and creatinine. • Food: acidic fruits or juices. High Risk Populations • Geriatrics

14. PENICILLIN Nursing Process • Assess allergy to penicillin or cephalosporin. • Interventions: don’t mix aminoglycosides w/ penicillin G, check for bleeding, monitor temperature, dilute IV antibiotic. • Evaluate effectivess of med by determining if infection ceased and whether SE have occurred. Client Education • encourage client to increase fluid intake • instruct client that chewable tablets must be chewed or crushed before swallowing • advise client to take medication with food to avoid GI irritation.

15. CEPHALOSPORIN Indications for Use Skin, urinary and respiratory infections. Can also treat genital, bone joint infections and endocarditis. Example DRUG • Cefazolin(Ancef), (Ketzol)

16. CEPHALOSPORIN (cont.) Side Effects Anorexia, NVD, rash, abdominal cramps AR: superinfections, urticaria LIFE THREAT: seizures (high doses), anaphylaxis Contraindications Hypersensitivity to this antibiotic, watch for PCN allergies. Renal disease, lactation for mothers

17. CEPHALOSPORIN (cont.) Interactions Drug: • ETOH • loop diuretics, aminoglycosides, • tetracyclines and erythromycin Lab: • BUN, serum creatinine, AST, ALT, ALP, LDG, and bilirubin. High Risk Populations • persons allergic to PCN may also be allergic to cephalosporins

18. CEPHALOSPORIN Nursing Process • record VS and urine output • check lab results especially those that indicate renal and liver function-report abnormal findings Client Education • advise client to ingest buttermilk or yogurt to prevent superinfection of the intestinal flora, • infuse IV cephalosporins over 30min

19. MACROLIDE Indications for Use For patients with PCN allergies treats gram positive and some gram negative bacteria, respiratory and skin infections and gonorrhea Example DRUG • Azithromycin (Zithromax), (AzaSite)

20. MACROLIDE (cont.) Side Effects SE: NVD,anorexia, rash, tinnitus, pruritus AR: hearing loss, vaginitis, superinfections, stomatitis LIFE THREAT: Hepatotoxicity, anaphylaxis Uncommon: abdominal Pain , diarrhea(p. 427) Contraindications Hepatic or renal dysfunction, hypersensitivity, lactaction

21. MACROLIDE (cont.) Interactions Drug: • digoxin, theophylline (bronchodilator), and warfarin (anticoagulant) • penicillins and clindamycin • antacids • clindamycinor lincomycin Food: • administer 1 h before or 2 h after meals. • fruit juice. High Risk Populations • Liver toxicity can occur if taken with high doses of other hepatogoxic drugs (acetaminophen), phenothiazines, and sulfonamides.

22. MACROLIDE Nursing Process • check lab tests to determine liver function, • obtain a Hx of drugs client takes-peak level of azithromycin may be decreased by antacids • Interventions: monitor vital signs and client for liver damage resulting from prolonged use • administer oral meds 1hr before or 2hrs after meals • do not give w/ fruit juice, dilute IV meds • administer antacids 2hrs before or 2hrs after azithromycin. Client Education • Instruct client to take the full course of antibacterial agent as prescribed. Drug compliance is most important for all antibacterials (antibiotics).

23. TETRACYLINE Indications for Use Treat both gram positive and gram negative bacteria, skin and respiratory infections, syphilis, gonorrhea, chlamydia, ricketts and rosacea Example DRUG • Doxycline (Vibramycin), (Vibra-Tabs)

24. TETRACYCLINE (cont.) Side Effects Abdominal discomfort, rash, HA, pruritus, color vision change, photosensitivity AR: superinfection and severe photosensitivity LIFE THREAT: Hepatotoxicity, blood dyscrasias, intracranial HTN, psuedomembranous colitis Contraindications Severe renal or hepatic disease, pregnancy, hypersensitivity, Caution: hypokalemia, bradycardia, alcoholics, antidysrythmics

25. TETRACYCLINE (cont.) Interactions • Drug: digoxin antacids, iron, and zinc, oral contraceptives, lithium levels • Lab: potassium level • Food: Dairy products (milk, cheese) High Risk Populations • teratogenic effects • children less than 8 should not use due to discoloration of permanent teeth

26. TETRACYCLINE Nursing Process • Assess vital signs and urine output-report abnormal findings, • check lab results especially renal and liver function • obtain a Hx of dietary intake and drugs client is currently taking. Interventions: • administer tetracycline 1hr before or 2 hrs after meals • monitor lab values for liver and kidney function • record VS and urine output. Client Education • Storage of tetracycline • expiration date • teratogenic effects • discoloration of permanent teeth in children <8, advise

27. AMINOGLYCOSIDE Indications for Use Gram-negative bacteria can cause serious infections. Treats PID, effective against methicillian-resistant and staphylococcus infections DRUG • Gentamicin Sulfate (Garamycin)

28. AMINOGLYCOSIDE (cont.) Side Effects Tremors, numbness, rash, muscle cramps or weakness, anorexia, visual disturbance AR: Oliguria, uticaria, palpations, superinfection LIFE THREAT: nephrotoxicity, agranulocytosis, neuromuscular block, ototoxicity and liver damage Contraindications Sever renal disease, hypersensitivity, lactation, pregnancy, Caution: renal disease, heart failure, myasthenia gravis, parkinsonism, older adults, neonates

29. AMINOGLYCOSIDE (cont.) Interactions • Drug: Increase risk of ototoxicity with loop diuretics, increase risk of nephrotoxicity with amphotericinB, furosemide, and vancomycin • Lab: Increase BUN, serum AST, ALT, LDH, bilirubin, creatinine, decrease serum potassium and magnesium High Risk Populations • Nephrotoxicity is dependent on drug dose, renal function, and age. Age: young and older clients should be assessed for signs of toxicity: hearing, balance, urinary output.

30. AMINOGLYCOSIDE Nursing Process • Assess VS and urine outpute and compare these results w/ future VS and urine output, assess renal function, liver function and electrolytes, assess Hx of renal or hearing disorders. • Interventions: Send sample to lab for C&S, monitor I&O, urinalysis may be ordered daily, check for hearing loss, monitor VS, and note if body temperature has decreased. Client Education • Unless fluids are restricted, encourage client to increase fluid intake. • Instruct client never to take leftover antibiotics.

31. FLOUROQUINOLONE Indications for Use Respiratory infections (moderate to severe), renal and bone infections DRUG • Levofloxacin (Levaquin)

32. FLOUROQUINOLONE (cont.) Side Effects Abdominal cramps, HA, fatigue, dizziness, restlessness, flushing, rash, flatulence, photosensitivity, tinnitus AR: Steven-Johnson syndrome, encephalopathy, dysrythmias, seizures, psuedo-membranous colitis. Contraindications Severe renal disease, hypersensitivity to other quinolones, breastfeeding, pregnancy Caution: renal disorders, children <14 or older adults, patients taking, theophylline, seizures

33. FLOUROQUINOLONE (cont.) Interactions • Drug: Increase effect of oral hypoglycemics, theophylline, and caffeine, decrease drug absorpotion with antacids and iron • Lab: Increase AST and ALT High Risk Populations • Diabetes Mellitus: monitor blood sugar. Levofloxacin can increase effects of oral hypoglycemics.

34. FLOUROQUINOLONE Nursing Process • Record VS and I&O-compare w/ future results, assess lab results for renal function, obtain a drug and diet Hx • Interventions: Send specimen to lab for C&S, monitor I&O, recortVS and report abnormal findings, check lab results for liver dysfunction, administer meds 2hrs before or after antacids and iron products, take w/ a full glass of water, if GI distress occurs, take w/ food, check serum theophylline levels, monitor blood sugar Client Education • Teach client to drink at least 6 to 8 glasses of fluid daily. Encourage client to avoid caffeinated products.

35. SULFONAMIDE Indications for Use • To treat urinary tract infection, otitis media, bronchitis, pneumonia, pneumocystis carinii; infection, rheumatic fever, burns DRUG • sulfamethoxazole-Trimethroprim/TMP-SMZ (Bactrim), (Septra)

36. SULFONAMIDE (cont.) Side Effects SE: Anorexia, rash, stomatitis, fatigue, depression, headache, vertigo, photosensitivity. AR: LIFE THREAT: leukopenia, thrombocytopenia, increased bone marrow depression, hemolytic anemia, aplasticanemia, agranulocytosis,Stevens-Johnson syndrome, renal failure Contraindications Severe renal or hepatic disease, hypersensitivity to sulfonamides

37. SULFONAMIDE (cont.) Interactions • Drug: Increase anticoagulant effect with warfarin, increase hypoglycemic effect with oral hypoglycemic drugs • Lab: May increase BUN, serum creatinine, AST, ALT, and ALP High Risk Populations • Clients with AIDS are more susceptible to TMP-SMZ toxicity

38. SULFONAMIDE Nursing Process • Assess client’s renal function, obtain medical and drug Hx, determine if client is hypersensitive to sulfonamides, assess baseline lab results especially CBC. • Interventions: Administer w/ a full glass of water, monitor VS, Observe client for hematologic reactions that may lead to life-threatening anemias, check for S&S of superinfection. Client Education • Instruct client to take several quarts of fluid daily, advise pregnant clients not to take during the last 3 months of pregnancy, inform client not to take antacids w/ sulfonamides, warn client who has an allergy to one sulfonamide that all sulfonamide preparations should be avoided, with health care provider’s approval, because of the possibility of cross sensitivity.

39. ANTIVIRAL Indications for Use There are groups of antiviral drugs effective against various viruses such as influenza A and B, herpes species, cytomegalovirus (CMV), and human immunodeficiency virus (HIV). DRUG • Purine Nucleosides- Acyclovir Sodium (Zovirax) • Systemic Non HIV- amantadine HCI (Symmetrel) • Neuraminidase Inhibitors- oseltamivir phosphate (Tamiflu)

40. ANTIVIRAL (cont.) Side Effects HA, tremors, lethargy, rash, pruritus, increased bleeding time, phlebitis at IV site AR: Uticaria, anemia, gingival hyperplasia. LIFE THREAT: neuropathy, seizures, nephrotoxicity (large doses), bone marrow depression, thrombocytopenia, leukopenia, granulocytopenia Contraindications Hypersensitivity, severe renal or hepatic disease. Caution: electrolyte imbalance, nursing mothers, young children

41. ANTIVIRAL (cont.) Interactions • Drug: Increase nephro-neurotoxicity with aminoglycosides, probenecid, and interferon • Lab: May increase AST, ALT, and BUN High Risk Populations • Cervical cancer is more prevelant in women with genital herpes, these women should have a PAP smear twice a year

42. ANTIVIRAL Nursing Process • Obtain a medical Hx from client of any serious renal or hepatic disease, determine baseline VS and a CBC to use for comparison of future results, assess baseline lab results for future comparison, assess baseline VS and urine output. • Interventions: Check clients CBC, record urine output, note VS especially BP, observe for S&S of SE, check for superinfection, dilute IV drug and administer over 60 min, never give acyclovir as a bolus (IV push). Client Education • Advise client to maintain adequate fluid intake to ensure sufficient hydration for drug therapy and increase urine output, instruct client w/ genital herpes to avoid spreading infection by practicing sexual abstinence or by using condoms, Direct clients taking zidovudine to have blood cell count monitored.

43. Quiz Time !!!!!

44. REFERENCES Ryan, K. J., Ray, C. G., (2004). Medical Microbiology: An introduction to infectious disease (4thed). New York, NY. McGraw-Hill, Unit 1.