Antimicrobial Atlas
Evidence-based antimicrobial
knowledge, organized.
A structured reference for antimicrobial agents, pathogens and stewardship — built for clinical pharmacists, physicians, microbiologists and students.
Using antimicrobials safely, effectively, and responsibly.
Antimicrobial stewardship (AMS) is an interprofessional effort focused on timely, appropriate antimicrobial use — improving outcomes for the individual patient while protecting the effectiveness of these drugs for everyone else.
World Health Organization
Antimicrobial stewardship (AMS) is defined as a coherent set of actions that promote the responsible use of antimicrobials. This definition can be applied at the individual, national, and global levels, and across human health, animal health, and environmental health.
Centers for Disease Control and Prevention
Antimicrobial stewardship is defined as the use of the right antimicrobial, for the right patient, at the right time, at the right dose, and for the right duration, causing the least harm to the patient and future patients.
Infectious Diseases Society of America
Antimicrobial stewardship refers to interventions designed to improve and measure the appropriate use of antimicrobials by promoting the selection of the optimal antimicrobial drug regimen, dose, duration of therapy, and route of administration.
The 8 Ds of Antimicrobial Stewardship
A practical framework for every antimicrobial decision. Tap a card to expand it.
Make the right clinical diagnosis.
Use the right antimicrobial drug according to the suspected or confirmed pathogen, infection site, allergies, resistance patterns, and patient-specific factors.
Use the right dose according to the infection, patient characteristics, renal/hepatic function, and other relevant factors.
Perform appropriate microbiological investigations to establish the etiologic agent whenever appropriate.
Narrow-spectrum therapy and/or adjust antimicrobial therapy when appropriate based on clinical response and microbiological results.
Administer antimicrobials only for the recommended duration.
Provide appropriate source control, including drainage of abscesses and removal of necrotic tissue or foreign material when required.
Implement infection-prevention and control measures to prevent transmission of infection.
AMS as a clinical decision framework
The same 8 Ds, arranged as the sequence a stewardship-minded clinician follows.
- 01
Diagnosis
- 02
Microbiological investigation
- 03
Right drug
- 04
Right dose
- 05
Right route
- 06
De-escalation
- 07
Right duration
- 08
Source control
- 09
Infection prevention & control
Antimicrobial agents
Penicillins
Beta-lactams that block cell-wall synthesis; foundational and widely combined with inhibitors.
Cephalosporins
Generational beta-lactams with broadening gram-negative coverage across generations.
Carbapenems
Broadest-spectrum beta-lactams, often reserved for resistant gram-negative infections.
Macrolides
Protein-synthesis inhibitors valued for atypical pathogen coverage.
Fluoroquinolones
DNA gyrase/topoisomerase inhibitors with broad oral bioavailability.
Aminoglycosides
Concentration-dependent agents requiring careful renal and ototoxicity monitoring.
Stewardship
Empirical antimicrobial therapy
Selecting a starting regimen before culture results return — through to de-escalation, IV-to-oral switch, dose and duration optimization.
Antibiotic database
Cephalosporin
Ceftriaxone
Label lists activity in vitro and in clinical infections against most isolates of many Gram-negative organisms (e.g. E. coli, K. pneumoniae, H. influenzae, N. gonorrhoeae, N. meningitidis), Gram-positive organisms (e.g. S. aureus, S. pneumoniae, S. pyogenes) and some anaerobes. No activity against Chlamydia trachomatis; most C. difficile strains are resistant.
Source-verified clinical information · Last reviewed: October 2026
References
- Ceftriaxone for Injection, USP in ADD-Vantage Vial — Full Prescribing Information, Hospira, Inc. (Pfizer) — FDA-approved product labeling (2017)
Glycopeptide
Vancomycin
Label lists activity in vitro and in clinical infections against most isolates of Corynebacterium spp., Enterococcus spp. (including E. faecalis), Staphylococcus aureus (methicillin-resistant and -susceptible), coagulase-negative staphylococci, Streptococcus gallolyticus and viridans group streptococci. Not active in vitro against Gram-negative bacilli, mycobacteria or fungi.
Source-verified clinical information · Last reviewed: October 2026
References
- Vancomycin Injection (GALAXY) — Full Prescribing Information, Baxter Healthcare Corporation — FDA-approved product labeling (2026)
Carbapenem
Meropenem
Label lists activity in vitro and in clinical infections against most isolates of E. faecalis (vancomycin-susceptible), methicillin-susceptible S. aureus, streptococci (S. agalactiae, penicillin-susceptible S. pneumoniae, S. pyogenes, viridans group), E. coli, H. influenzae, K. pneumoniae, N. meningitidis, P. mirabilis, P. aeruginosa, and Bacteroides and Peptostreptococcus spp. No in vitro activity against MRSA or methicillin-resistant S. epidermidis.
Source-verified clinical information · Last reviewed: October 2026
References
- Meropenem for Injection, USP (I.V.) — Full Prescribing Information, Hospira, Inc. (Pfizer) — FDA-approved product labeling (2022)
Macrolide
Azithromycin
Label lists activity in vitro and in clinical infections against most isolates of S. aureus, S. agalactiae, S. pneumoniae, S. pyogenes, H. ducreyi, H. influenzae, M. catarrhalis, N. gonorrhoeae, Chlamydophila pneumoniae, Chlamydia trachomatis and Mycoplasma pneumoniae. Cross-resistance with erythromycin is demonstrated.
Source-verified clinical information · Last reviewed: October 2026
References
- ZITHROMAX (azithromycin) tablets and for oral suspension — Full Prescribing Information, Pfizer Inc. — FDA-approved product labeling (2026)
Microbiology & pathogens
Gram-positive
Thick peptidoglycan cell wall retaining crystal violet stain; includes staphylococci, streptococci and enterococci (demo).
Gram-negative
Thin peptidoglycan layer with an outer membrane; includes Enterobacterales and non-fermenters like Pseudomonas (demo).
Anaerobes
Organisms that grow without oxygen, relevant in intra-abdominal and odontogenic infections (demo).
Culture
Growing organisms from a clinical specimen to identify the causative pathogen and guide targeted therapy (demo).
MIC
Minimum inhibitory concentration — the lowest antibiotic concentration that prevents visible growth (demo).
Susceptibility
Interpretation of MIC against breakpoints to classify an isolate as susceptible, intermediate or resistant (demo).
Clinical tools
Resistance Atlas
Browse resistance mechanisms — ESBL, AmpC, MRSA, VRE and carbapenem resistance.
Renal Dose Calculator
Future tool: adjust dosing regimens against renal function tiers.
Resources & references
WHO
World Health Organization — AMS guidance
Global antimicrobial stewardship policy and technical guidance.
CDC
CDC — Core Elements of Antibiotic Stewardship
Core elements for hospital, outpatient and nursing home stewardship programs.
IDSA
IDSA — Stewardship guidelines
Clinical practice guidelines for implementing an antimicrobial stewardship program.