Most Commonly Prescribed Antibiotics Kristina Nelson PharmD Candidate Class of 2012 Kmj87@uw.edu
DeﬁnitionsAntimicrobial Substance that kills or inhibits the growth of microorganisms like bacteria, fungi and protozoaAntibacterial Substance that kills or inhibits the growth of bacteriaBacteriostatic Inhibits the growth or reproduction of bacteriaBactericidal Acts by killing bacteria
Deﬁnitions URI LRI AOM CAP ABS HAP PharyngitisCDAD PCP Pseudomembranous colitis MAC Cellulitis Bacterial vaginosis UTI
General Antibiotic Counseling TipsMost important: Take all antibiotics until they are gone!! Why...?General side eﬀects: N/V/D and yeast infections (women) What can you recommend to your patients? Take with food (drug permitting) OTC anti diarrhea meds (except when?) Probiotics?
General Antibiotic Counseling Tips Usual length of therapy is 5 to 14 days Some are less, some are more When will they feel better? Exception: azithromycin So what about oral contraceptives? Very controversial...
General Antibiotic Counseling Tips AllergiesYour ﬁrst question for the patient when they say they have an allergy... ????Penicillin allergies are very common and come in 3 varieties: Immediate (30-60 minutes) Accelerated (1-72 hours) Delayed (>72 hours) What should the patient look for and do??
General Storage and AdministrationShake suspensions well before each use Watch out for those that need to be refrigerated Check the stability of the drug after reconstitution vs. the length of therapyTablets- cool, dry placeWhat if they miss a dose?
Beta-lactamsPenicillins and Cephalosporins Mechanism and Site of Action Penicillin binding proteins in the bacterial cell wall and inhibits cell wall synthesis Bactericidal
Beta-lactams PenicillinsPenici!in VK, amoxicillin, amoxici!in/clavulanat" Tablets, chewable tablets, capsules, suspension Brand names: Veetids, Amoxil, Augmenti#Indications : Pharyngitis, AOM, ABS, CAP, UTIs, cellulitisSpecial administration: PCN- without food Dosing is usually BID-QID Amox- with or without Amox/clav- with food
Beta-lactams CephalosporinsCephalexin, cefuroxime, cefdinir Tablets, capsules, suspensions Brand names: Keﬂex, Ceftin, OmnicefIndications: Cellulitis, gonorrhea, AOM, ABS Special administration: Most are ok with or without food, Dosing usually some suspensions vary BID -QID Cefdinir - Not with antacids or iron containing supplements
Beta-lactamsSide eﬀects: N/V/D, yeast infections N/V/D is especially common with clavulanate So why do we use it?Allergic reactions What does a penicillin allergy mean for cephalosporins? What does a cephalosporin allergy mean for penicillins? Rash vs. Anaphylaxis
SulfonamidesMechanism and Site of Action Competes with enzyme required for folate synthesis in bacterial cell and slows cell cycle Bacteriostatic
SulfonamidesSulfamethoxazole/Trimethoprim Tablets, suspension SS and DS Brand name: Bactrim, Septra, SulfatrimIndications: uncomplicated UTIs, AOM, PCPSpecial administration: Best taken with food Full glass of water Dosing usually BID Suspension should not be refrigerated
SulfonamidesSide eﬀects: N/V/D Sun sensitivity, dizziness, rash Allergies: urticaria, Stevens-Johnson SyndromeShould not be used in pregnant women >38 weeks, lactating women or infants <2 monthsDrug interactions: methotrexate, warfarin, rosiglitazone
MacrolidesMechanism and Site of Action 50S ribosome subunit Binds ribosome and inhibits protein biosynthesis Bacteriostatic
MacrolidesAzithromycin, erythromycin, clarithromycin Tablets, suspensions, (ophthalmic) Brand name: Zpak, Ery-Tab, BiaxinIndications: CAP, URI/LRI, chlamydia, MAC, (conjunctivitis)Special administration: Best without food, but Dosing: Azithromycin-QD okay Clarithromycin-BID Erythromycin- BID-QID Azithromycin-antacids Clarithromycin and erythromycin-grapefruit
MacrolidesSide eﬀects: N/V/D, yeast infections Clarithromycin: metallic taste, sun sensitivity Azithromycin: normal side eﬀects, especially in high single-dose regimens Potential for QTc prolongation with allDrug interactions: all are P450 inhibitors and substrates Some key drugs to watch for: warfarin, digoxin, amiodarone, statins Clarithromycin worst oﬀender for DDIs
FluoroquinolonesMechanism and Site of Action Inhibits DNA replication & transcription by binding enzymes in the bacterial cell Bactericidal
FluoroquinolonesCiproﬂoxaci", levoﬂoxacin, moxiﬂoxacin Tablets, suspension Brand names: Cipro, Levaquin, AveloxIndications: Pyelonephritis , UTIs, CAP, ABSCipro- anthrax post exposure prophylaxisSpecial administration: With or without food - separate Dosing is QD-BID antacids, iron, MVTs and dairy
FluoroquinolonesSide eﬀects: N/V/D, yeast infections Sun sensitivity, headache, dizziness, dyspepsia Increased blood sugar in DM RARE- tendon toxicityDrug interactions: Cipro and caﬀeine Warfarin
TetracyclinesMechanism and Site of Action 30S ribosome subunit Binds ribosome and inhibits protein biosynthesis Bacteriostatic
TetracyclinesTetracycline, doxycycline, minocycline Tablets, capsules Brand names: Sumycin, Vibramycin, MinocinIndications: acne, skin infections, STDs, (respiratory infections)Special administration: Doxycycline and minocycline- Tetracycline- without with or without food food All with a full glass of water Dosing is usually BID-QID and sit up for 30 minutes Patients should never use Avoid antacids, iron, MVT and expired medication dairy
TetracyclinesSide eﬀects: N/V/D, yeast infections Sun sensitivity, headache, indigestion, teeth discolorationShould not be used in children <8 or pregnant womenDrug interactions: Doxycycline and warfarin
LincosamidesMechanism and Site of Action 50S ribosome subunit Binds ribosome and inhibits protein biosynthesis Bacteriostatic
LincosamidesClindamycin Capsules, suspension, topical Brand name: CleocinIndications : anaerobic upper GI infections, bacterial vaginosis, topical for acneSpecial administration: Full glass of water Dosing usually TID With or without food
LincosamidesSide eﬀects: N/V/D, yeast infections Diarrhea- higher risk for C. diﬃcile associated diarrhea and Pseudomembranous colitis (Black Box) Use of probioticsDrug interactions: very few!!
NitroimidazolesMechanism and Site of Action Absorbed into anaerobic and protozoal cells where converted into toxic compound that causes loss of helical DNA structure and strand breakage Bactericidal
NitroimidazolesMetronidazole Tablets, topical (vaginal) Brand name: FlagylIndications: anaerobic lower GI infections, C. diﬃcile associated diarrhea, bacterial vaginosisSpecial administration: Take with food or milk (except ER) Dosing usually TID Disulﬁram-like reaction (BID-QID) with alcohol
NitroimidazolesSide eﬀects: Metallic taste, discolored/dark urine, dysuria, dry mouthShould not be used in pregnant women in the ﬁrst trimesterDrug interactions: lithium
NitrofurantoinMechanism and Site of Action Inhibition of acetyl CoA interfering with the metabolism of carbohydrates in susceptible bacteria Bacteriostatic
NitrofurantoinNitrofurantoin Capsules Brand names: Macrobid and MacrodantinIndications: uncomplicated UTIs, and UTI prophylaxisSpecial administration: Take with food Dosing is usually BID
NitrofurantoinSide eﬀects: N/V/D, ﬂatulence, headache, discoloration of urineShouldnt be used in renal impairment, low/no systemic absorptionDrug interactions: Magnesium salts decrease eﬀectiveness
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