How the dose is calculated
Ceftazidime is dosed in mg/kg/day divided every 8 hours. Severe infections, including those needing reliable anti-pseudomonal cover (e.g. febrile neutropenia, cystic fibrosis exacerbations), use a higher total daily dose at the same frequency. This is an injectable (IV/IM) antibiotic — no suspension volume conversion applies.
Typical dosing by indication
| Indication | Dose | Frequency | Max |
|---|---|---|---|
| Standard | 100 mg/kg/day | every 8h (3×/day) | 6000 mg/day |
| Severe/pseudomonal | 150 mg/kg/day | every 8h (3×/day) | 6000 mg/day |
Ceftazidime is supplied as a powder for reconstitution (IV/IM) — there is no oral suspension, so this calculator reports the mg dose only; follow your local pharmacy's reconstitution and infusion protocol for the actual volume to administer.
Clinical use
- Ceftazidime's standout feature is reliable activity against Pseudomonas aeruginosa, making it a preferred third-generation cephalosporin for pseudomonal infections, febrile neutropenia, and cystic fibrosis pulmonary exacerbations.
- Weaker Gram-positive activity than other third-generation cephalosporins (notably against Streptococcus pneumoniae and Staphylococcus aureus) — not a good empirical monotherapy choice when Gram-positive coverage is also needed.
- Often combined with an aminoglycoside for synergy in serious pseudomonal infections.
- Requires dose-interval adjustment in significant renal impairment.
Frequently asked questions
What is ceftazidime used for?
Ceftazidime is a cephalosporin with strong activity against Pseudomonas aeruginosa, commonly used for febrile neutropenia, cystic fibrosis pulmonary exacerbations, and other serious infections where pseudomonal cover is needed.
Why is ceftazidime sometimes combined with another antibiotic?
Its Gram-positive coverage is weaker than other cephalosporins, so it's often combined with an aminoglycoside or another agent for broader coverage or synergy in serious pseudomonal infections.
Is ceftazidime effective against Staphylococcus aureus?
Not reliably — ceftazidime has weaker Gram-positive activity than other third-generation cephalosporins, so a different agent is preferred if Staphylococcus aureus is a significant concern.
Is ceftazidime available as a tablet or syrup?
No — ceftazidime is only available as an injectable (IV or IM) formulation; there is no oral tablet or suspension form.
References
- Freifeld AG, et al. Clinical Practice Guideline for Antimicrobial Prophylaxis and Empiric Therapy in Febrile Neutropenia (IDSA). Clin Infect Dis. 2011.
- British National Formulary for Children (BNFc) — Ceftazidime.
- Cystic Fibrosis Foundation. Pulmonary Guidelines — Treatment of Pulmonary Exacerbations.