What is the standard dosage of ceftazidime (intravenous) for a patient with a urinary infection and normal renal function?

Standard Ceftazidime IV Dosage for Urinary Tract Infection

For uncomplicated urinary tract infections in patients with normal renal function, administer ceftazidime 250 mg IV every 12 hours; for complicated UTIs, use 500 mg IV every 8-12 hours. 1

Dosing Based on UTI Complexity

Uncomplicated UTI

• 250 mg IV every 12 hours is the FDA-approved dose for uncomplicated urinary tract infections 1
• This lower dose has demonstrated adequate efficacy in clinical trials, with cure rates comparable to higher doses for simple infections 2

Complicated UTI

• 500 mg IV every 8-12 hours is recommended for complicated urinary tract infections 1
• Complicated UTIs include those with structural abnormalities, immunosuppression, pregnancy, diabetes, male patients, or presence of resistant organisms 3
• The every-8-hour interval provides more consistent drug levels for difficult-to-eradicate infections 1

Treatment Duration

• Continue therapy for 5-7 days for most complicated UTIs 4
• Treatment may extend to 10-14 days if source control is difficult or if pyelonephritis is present 4, 3
• Therapy should continue for 2 days after signs and symptoms resolve, though complicated infections may require longer courses 1

Renal Function Adjustments

Critical caveat: Ceftazidime is excreted almost exclusively by glomerular filtration, requiring dose reduction in renal impairment 1, 5

Dosing by Creatinine Clearance:

• CrCl 50-31 mL/min: 1 gram every 12 hours 1
• CrCl 30-16 mL/min: 1 gram every 24 hours 1
• CrCl 15-6 mL/min: 500 mg every 24 hours 1
• CrCl <5 mL/min: 500 mg every 48 hours 1

Hemodialysis Patients:

• Give 1 gram loading dose, followed by 1 gram after each hemodialysis session 1

Clinical Considerations

Pathogen Coverage

• Ceftazidime provides excellent coverage for Gram-negative organisms including E. coli, Klebsiella, Enterobacter, and Pseudomonas aeruginosa 2
• Lower cure rates (53-64%) occur with Pseudomonas and Proteus species, particularly in complicated infections, which may warrant higher dosing or combination therapy 2

Resistance Patterns

• Obtain urine culture before initiating therapy to guide targeted treatment, especially in complicated UTIs where resistance is more likely 3, 6
• Local resistance patterns should guide empiric selection 3
• For carbapenem-resistant Enterobacterales causing UTI, ceftazidime-avibactam 2.5 g IV every 8 hours is preferred over ceftazidime alone 4

Route of Administration

• Ceftazidime may be given IV or by deep IM injection into large muscle mass 1
• Avoid intra-arterial administration 1