Adult antibiotic & antifungal dosage & route

Always consider

Allergy
Adaptation to renal insufficiency or liver dysfunction
When possible, consider continuous perfusion for more severe cases (ceftazidime, cefotaxime, cefepime, meropenem, piperacillin-tazobactam)
Highest dosage in case of sepsis, neutropenia, difficult to treat bacteria (ESBL, pseudomonas)

Antibiotic	Dosage
Amikacin	30mg/kg/d in 1 dose if severity
Amoxicillin	100-200mg/kg/day Intravenous: in 4–6 doses
Aztreonam	2g every 8 hours (infuse in same time when co-administered with Ceftazidime-avibactam, each in a 3-hours infusion
Cefazolin	100mg/kg/d in 3 doses
Cefepime	6 to 8 g/d Intravenous: in 3 or 4 doses
Cefiderocol	2 g intravenously every 8 hours over 3 hours
Cefotaxime	3 to 6g/d in 3 doses If meningitidis: 200-300mg/kg/d in 6 doses or continuous infusion
Ceftazidime	3 to 6 g/d Intravenous: in 3 doses
Ceftazidime-avibactam	2.5 g (Ceftazidime 2 g + Avibactam 0.5 g) intravenously every 8 hours (3-hours infusion each)
Ceftriaxone	1 to 2 g/day Intravenous: in 1 dose If meningitidis: 75-100 mg/kg/d in 2 doses
Ciprofloxacin	Oral: 500-750 mg every 12 hours Intravenous: 400 mg every 8-12 hours
(Cl)oxacillin	150mg/kg, divided in 4 doses Maximum 12g/d
Daptomycin	10 mg/kg/day Intravenous: in 1 dose
Doxycycline	100 mg/12h
Gentamicin	If sepsis: 6-8 mg/kg/day in one dose, 48h until antibiogram If endocarditis due to enterococcus or staphylococcus: 3 mg/kg/day Intramuscular injection or intravenous in 1 dose
Imipenem	500mg/6h – 1g/8h
Imipenem-relebactam	1.25g (Imipenem 500 mg + Cilastatin 500 mg + Relebactam 250 mg) intravenously every 6 hours over 30 minutes
Levofloxacin	500–750 mg once daily depending on the severity and type of infection, oral or intravenous
Linezolid	600mg/12h Oral or intravenous
Meropenem	1 g/8h (If meningitis 2g/8h)
Meropenem-vaborbactam	4g (Meropenem 2 g + Vaborbactam 2 g) intravenously every 8 hours (3-hours infusion each)
Metronidazole	500mg/8h Oral or intravenous
Penicillin G	12-18 millions U/day either in 4-6 doses or continuously
Piperacillin-tazobactam	12g/d in 3 dose to 16g/d in 4 doses (if Pseudomonas, neutropenia, ESBL if the MIC is ≤ 8 mg/L)
Trimethoprim/Sulfamethoxazole	Standard dosing: 800 mg sulfamethoxazole / 160 mg trimethoprim every 12 hours Stenotrophomonas maltophilia: 8-12mg/kg/d of TMP content
Vancomycin	15 mg/kg/j en 1 h, bid (max. 4 g/j) If septic shock or intravascular device infection: 40 mg/kg/day IV Intravenous(max : 4g/d), continuous infusion (after a loading dose of 30 mg/kg bolus over 2 hours) in a dedicated central venous catheter (venotoxicity)

Antibiotic	Dosage
Amphotericin B Deoxycholate Note: Amphotericin B deoxycholate is generally less preferred due to its higher toxicity profile compared to liposomal formulations.	0.5–1 mg/kg/day Intravenous: 2 hours infusion Require close monitoring for nephrotoxicity and infusion-related reactions Administer preferably via a central line (if such access is available) Gently agitate the syringe before administration Flush with D5% or D10% before the dose Administer over 2 hours Slowly flush with D5% or D10% after the dose Incompatible with normal saline (NaCl)
Caspofungine	Normal dose: Day 1: 70mg day Intravenous: in 1 dose From day 2: 50 mg and if weight >80 kg keep 70mg/day intravenous
Fluconazole	12mg/kg/d day 1 then 6mg/kg/d from day 2, PO or IV, max 1200mg/d If endocarditis: 150 mg/j +/- 5FC 25 mg/kg x 4/ j
Liposomal Amphotéricine B	Normal dose: 3 mg/kg/d Intravenous: in 1 dose If endocarditis: consider 3-5 mg/kg/d +/- 5FC 25 mg/kg x 4/d