Antibiotics PCN Danita Dee Narciso Pharm D 1 2 Objectives - PowerPoint PPT Presentation

UH Hilo School of Nursing NURS 203 General Pharmacology Antibiotics PCN Danita Dee Narciso Pharm D 1

2 Objectives  Recognize the signs and symptoms of infection  Become familiar with antibiotics that are commonly used and recognize areas of potential practical conflicts  Recognize antibiotics that have interactions with psychoactive medications or illnesses  Learn how to monitor for and adjust for changes in drug levels due to interactions with antibiotics

3 Introduction  Signs and symptoms of infection  Fever  WBC increases  Normal = 4,000 – 10,000 cells/mm 3  Increases in lymphocytes ~ TB, viral, or fungal infections  Increases in monocytes ~ TB or lymphoma  Increases in eosinophills ~ Allergy  Local signs  Pain, swelling, redness, tenderness, purulent discharge

4 Fever (pyrexia)  Normal – 98.0-98.6º F (36.7-37ºC)  Rectal - 1ºF or 0.6ºC higher  Axillary - 1ºF or 0.6ºC lower  Hyperpyrexia  Hypothermia  Other Causes  Trauma  Malignancy  Infarctions  Blood disorders  Various drugs  Immune disorders  False positives  False negatives

5 Drug induced fever  Beta lactams  Anticonvulsants  Allopurinol (Zyloprim) – Gout  Hydralazine – Blood pressure  Nitrofurantoin (Macrobid) – UTI  Sulfonamides  Phenothiazines  Methyldopa – Blood pressure in pregnancy

6 Drug induced fever  Sulfonamides  Phenothiazines  Sulfamethoxazole  Promethazine  Diuretics  Chlorpromazine (Thorazine)  Anticonvulsants  Thioridazine  Celecoxib (Mellaril) (Celebrex)  Prochlorperazine  Sumatriptan (Compazine) (Imitrex) False positives, false negatives???

7 Penicillin

8 Terms  Bactericidal  Bacteriostatic  Beta-lactam antibiotics  Beta-lactamases (penicillinase)  Penicillin binding proteins (PBPs)  Peptidoglycan  Transpeptidases

9 Penicillin – a beta-lactam antibiotic

10 Penicillin (PCN)  Bactericidal vs bacteriostatic  MOA  Bind to PBPs, inhibit the reaction (transpeptidase reaction) that cross links the peptidoglycan chain on the bacterial cell wall, and activate autolytic enzymes  Time dependent killing  The bacteria’s defense  Penicillinase (beta-lactamases)  Changes in PBPs

11 Penicillins  Natural pcn  Penicillin G…  Penicillin VK  Mild to moderate infection without bacteremia of the skin and respiratory tract  Gonorrhea – IM  Syphilis - IM  Neurosyphilis – IM/IV  Pharyngitis  URI

12 Penicillins  Penicillinase resistant  Oxacillin  Dicloxacillin  Nafcillin  MSSA infections  Erysipelas  Skin abscess  CNS infections – PCN can penetrate inflamed meninges

13 Penicillins  Aminopenicillins  Amoxacillin  Ampicillin  May be used in combination with a beta-lactamase inhibitor  Augmentin – amoxicillin and clavulanic acid  Unasyn – ampicillin and sulbactam  Sinus infection  Dental prophylaxis  ENT and genitourinary infection  Hpylori  UTI  Meningitis

14 Penicillins  Extended spectrum (Carboxypenicillins/ureidopenicillins)  Ticarcillin  Piperacillin  Used in combination with a beta-lactamase inhibitor  Zosyn – piperacillin and tazobactam  Timentin – ticarcillin and clavulanic acid  IV – UTI, systemic infections, complicated abdominal infections, etc…

15 PCN - Kinetics  Absorption  Oral depends on pH  Distribution  Lungs, liver, kidneys, muscle, bone, placenta, and urine  Metabolism  Liver – limited and converted to inactive metabolites  Excretion  Mostly (60%) unchanged in the urine – monitor renal function  Bile – nafcillin and oxacillin

16 Adverse drug reactions  GI disturbances  Nausea, diarrhea, black hairy tongue (ampicillin),  Dermatologic  Rash and redness  CNS  Agitation, anxiety, seizure, confusion, and behavioral changes  Psudomembranous cholitis – extended spectrum and aminoPCNs  Liver toxicity - oxacillin  Be aware when a patient has recently started a penicillin

17 Drug-drug interactions  Probenecid  Increase PCN concentrations  Methotrexate  PCNs reduce tubular secretion  Tetracycline  May reduce the effectiveness of PCNs  Chloramphenicol  May reduce the effectiveness of PCNs  Neomycin  Decreases the absorption of some PCNs  Hormonal contraception  Effectiveness is reduced with the use of some PCNs  Anticoagulants  PCNs may increase the bleeding risk

18 Allergy  Allergy is the most common ADR related to penicillins and can range from itching, fever, and rash to nephritis and anaphylaxis  An allergic reaction may occur 1 – 2 weeks after an injection (serum sickness)  Oral allergy may present as  Tongue swelling  Nausea, vomiting, or diarrhea

19 Resistance (Saving our big guns for big bugs)  Identify the organism  Empiric therapy in some cases

20 PCN and UTI  Signs and symptoms  General  Lower UTI  Painful urination, urgency, frequency, nocturia, blood in urine, and suprapubic heaviness  Upper UTI  Flank pain, fever, nausea, vomiting, and muscle weakness  Elderly  Altered mental status, change in eating habits, or GI symptoms  Indwelling catheters and neurologic disorders  Usually develop upper UTI with bacteremia due to the absence of symptoms

21 Questions  ?????????????????????????????????? ?????????????????????????????????? ?????????????????????????????????? ?????????????????????????????????? ?????????????????????????????????? ?????????????????????????????????? ?????????????????????????????????? ?????????????????????????????????? ??????????????????????????????????