Antibiotics

1 In patients requiring antibiotic therapy, make rational choices (i.e., first-line therapies, knowledge of local resistance patterns, patient’s medical and drug history, patient’s context).

H Pylori Infection – 1st line Tx:

• Amoxicillin 1g bid + Clarithromycin 500mg bid + Pantoprazole 40mg bid x 7 days
• Alt: Metronidazole 500mg bid + Clarithromycin 500mg bid + Pantoprazole 40mg bid x 7 days

C. Difficile infection

• Mild to Moderate (WBC<15, SCr
• Metronidazole 500mg tid x 10-14 days
• Severe (WBC >15, SCr >1.5x baseline)
  • Vancomycin (40mg/kg/d div 3 or 4) 125mg qid x 10-14days

Traveller’s Diarrhea

• Avoid anti-motility (loperamide) if F/C, bloody diarrhea
• Avoid quinolones in <16yo
• Prevention:
  • Pepto 2 tabs or 30 mL qid with meals and in evening
  • Cirpofloxacin 500mg daily
• Mild to Moderate (<3BM/d, no blood, no f/c)
  • Loperamide 4mg x 1 then 2mg after each BM (max 8/d)
  • Pepto 2tabs or 30mL, repeat q30min (max 8/d)
• Severe (>3BM/d or blood or f/c)
  • Ciprofloxacin 750mg daily x 1-3d

Endocarditis prophylaxis

• Pt with prosthetic valve, previous bacterial endocarditis, unrepaired cyanotic congenital heart valve, cardiac transplant recipient
• Procedure: dental req gingival manipulation, derm procedure, cystoscopy, tonsillectomy, adenoidectomy, bronchoscopy
• Amoxicillin 2g po x 1 – 1hr before the procedure

Epididymitis – Tx 10-14 days

• >35yo: Ciprofloxacin 500mg bid or extended release 1g daily

Prostatis – Tx 2-4 wk after symptoms have resolved

• Ciprofoxacin 500mg bid or extended release 1g

Trichomoniasis – Tx all cases and sexual partners

• Metronidazole 2g daily or 500mg bid x 7 days

BV (bacterial vaginosis)

• Metronidazole 500mg bid x 7 days (10-14 days if recurrent)

Genital Herpes

• Valacyclovir 500mg bid (5-7 days if acute & prophylaxis at 36 wk & 3 days if acute recurrent)
• Valacyclovir 500mg daily for chronic suppressive (>6/yr)

External Genital Warts

• Cryotherapy q1-2wk
• Podophyllin 10-25% applied weekly, wash off after 1-4 hr
• TriChloroAcetic acid 80-90% in 70% ethyl alcohol weekly prn
• Imiquimod 5% crm qhs 3/wk x 16 wk, wash off after 6-10hr
• Podofilox 0.5% bid x 3 d, repeat x 4 prn
• Laser
• Surgical

Cervicitis

• Cefixime 800mg + Azithromycin 1g x1

PID

• Cefixime 800mg x 1 or ceftriaxone 500mg IM x 1 AND Doxycycline 100mg bid x 14 days
• Add Metronidazole 500mg bid x 14 d
  • if adnexal mass, abscess, peritonitis or BV

Urethritis

• Cefixime 400mg x 1 or Ceftriaxone 250mg IM x 1 AND Azithromycin 1g x 1 or Doxycycline 100mg bid x 7 days

Vulvovaginal Candidiasis – use topical in pregnancy

• Acute:
  • Clotrimazole 500mg PV x 1 or 200mg PV x 3 days
  • Fluconazole 150mg po x 1
• Recurrent (>=4/yr)
  • Fluconazole 150mg po q3d x 3 doses then Fluconazole 150mg po q1week x 3-6mo

COPD exacerbation

• Simple (FEV1>50, mild-mod, =
• Clarithromycin 500mg bid or 1000mg extended daily x 5 days
• Complicated (FEV1<50, >=4/yr, cardiac dz)
  • Levofloxacin 750mg daily x 5 days
  • Amoxicillin/Vlavulanate 875mg bid x 7-10 days
•  Pseudomonas (FEV1<35, chronic steroids, constant purulent sputum)
  • Ciprofloxacin 500-750mg bid x 7-10 days

Otitis Externa

• No perforation
  • Buro-sol Otic solution 2-3 drops qid x 5 days
• Perforation
  • Cirpdex otic suspension 4 drops bid x 5 d
• Fungal
  • Clotrimazole 1% crm apply bid x 5 d

Otitis media – 10 d if 2yo

• Amoxicilin 80mg/kg/d div 2-3 (max 3g/d)
• Chronic perforation
  • Ciprodex otic suspension 4 drops bid x 5 days

Pertussis

• Clarithromycin 500mg bid x 5-7 days

Pharyngitis (majority viral)

• Amoxicillin 40mg/kg/d div 2-3 x 10 days

Sinusitis

• Amoxicillin 500mg tid x 5-10d
• Peds: Amoxicillin 800mg/kd/d div 2-3 (max 3g/d)

Pneumonia

• Clarithromycin 500mg bid or 1g-extended daily x 7-14 days
• Amoxicillin 1g tid, Erythromycin 500mg qid, Azithromycin 500mg x 1 hen 250mg x 4 days)
• Corbidities or Long term care
  • Moxifloxacin 400mg daily x 7-14 days
  • Levofloxacin 750mg daily x 5 days
• Suspected aspiration
  • Amoxicillin/Clavulanate 875mg bid x 7-14 days

Influenza

• post-exposure prophylaxis within 36hr: Oseltamivir 75mg x 10 d
• Tx within 36hr: Oseltamivir 75mg bid x 5d

Cellulitis – Tx 7-14 days

• Mild and uncomplicated: Keflex 500mg qid
• Severe and uncomplicated: Clindamycin 450mg qid
• Face and complicated: ceftriaxone 1g IV/IM daily (75mg/kd/d – peds)
• Diabetic foot (not limb threatening): Keflex 500mg qid + metronidazole 500mg bid
• Diabetic foot (limb threatening): ceftriaxone 2g IV/IM + Metronidaole 500mg bid x 14-28 days or 4-12 weeks if osteomyelitis

Bites

• Amoxicillin/Clavulanate 875mg bid x 7-14days

Cutaneous infections

• Folliculitis + furuncle (boil): Hot compresses and anti-septic
• Carbuncles (mod to severe): keflex 500mg qid
• Complicated (peri-rectal abscess): Ciprofloxacin 750mg bid
  • consider adding metronidazole 500mg bid

Impetigo

• Mupirocin 2% apply tid x 7 days
• Fusidic acid 2% tid-qid x 7 days
• Keflex 500mg qid x 7-10days

Lyme dz

• Amoxicillin 500mg tid x 14-21 days
• Doxycycline 100mg bid x 14-21 days

MRSA

• Moderate:
  • Clindamycin 400mg qid
  • Doxycycline 100mg bid (not for children <8)
• Severe
  • Vancomycin 1g bid IV
  • Linezolid 600mg bid

Onychomycosis 12-16 wk for toe and 6 wk for finger

• Terbinafine 250mg daily
• Penlac daily x 48wk

Shingles (Varicella Zoster) – initiate within 72hr of onset of rash

• Valacyclovir 1g tid x 7-14 days

Cystitis or Asymptomatic bacteuria in Pregnancy

• Macrobid 100mg bid x 5 days (7-14 days if recurrent <1mo)

Pyelonephritis / Complicated UTI

• Ciprofloxacin 500mg bid or 1g -extended x 7-14 days

Malaria Prophylaxis (certain regions are resistant to Mefloquine or Chloroquine)

• Malarone (Atovaquone-Proguanil) 1 d before till 1 wk after
• Doxycycline 1 d before till 4 wk after
• Mefloquine 1wk before till 4 wk after
• Chloroquine 1 wk before till 4 wk after

2 In patients with a clinical presentation suggestive of a viral infection, avoid prescribing antibiotics.

Viral features include conjunctivitis, cough, hoarseness, coryza, anterior stomatitis

3 In a patient with a purported antibiotic allergy, rule out other causes (e.g., intolerance to side effects, non-allergic rash) before accepting the diagnosis.

4 Use a selective approach in ordering cultures before initiating antibiotic therapy (usually not in uncomplicated cellulitis, pneumonia, urinary tract infections, and abscesses; usually for assessing community resistance patterns, in patients with systemic symptoms, and in immunocompromised patients).

5 In urgent situations (e.g., cases of meningitis, septic shock, febrile neutropenia), do not delay administration of antibiotic therapy (i.e., do not wait for confirmation of the diagnosis).

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Reference:

• 2013 Anti-infective guidelines for community acquired infections