Is ciprofloxacin (Cipro) renally cleared, meaning is it primarily excreted by the kidneys?

From the Guidelines

Ciprofloxacin is indeed renally cleared, with approximately 40-50% of the drug excreted unchanged in the urine, necessitating dose adjustments in patients with impaired kidney function. According to the guidelines for preventing opportunistic infections among HIV-infected persons 1, the dosing of ciprofloxacin needs to be adjusted based on renal function. For patients with creatinine clearance between 30-50 mL/min, the dose should be reduced to 250-500 mg every 12 hours, and for those with creatinine clearance less than 30 mL/min, the dose should be further reduced to 250-500 mg every 18 hours. Additionally, for patients undergoing hemodialysis, the dose should be administered after each dialysis session. This highlights the importance of considering renal function when prescribing ciprofloxacin to avoid potential toxicity and ensure effective treatment. Key points to consider include:

• Dose adjustment based on creatinine clearance
• Reduced dosing for patients with impaired kidney function
• Administration after dialysis for patients undergoing hemodialysis
• Importance of monitoring renal function during therapy, especially in elderly patients or those with pre-existing kidney disease.

From the FDA Drug Label

The serum elimination half-life in subjects with normal renal function is approximately 4 hours Approximately 40 to 50% of an orally administered dose is excreted in the urine as unchanged drug. The renal clearance of ciprofloxacin, which is approximately 300 mL/minute, exceeds the normal glomerular filtration rate of 120 mL/minute. Ciprofloxacin is eliminated primarily by renal excretion; however, the drug is also metabolized and partially cleared through the biliary system of the liver and through the intestine.

Ciprofloxacin is renally cleared. Approximately 40 to 50% of an orally administered dose is excreted in the urine as unchanged drug, and the renal clearance of ciprofloxacin exceeds the normal glomerular filtration rate, indicating that active tubular secretion plays a significant role in its elimination 2.

From the Research

Ciprofloxacin Renal Clearance

• Ciprofloxacin is renally cleared, with its clearance decreasing in relation to the degree of renal impairment 3.
• The renal clearance of ciprofloxacin is linearly related to the glomerular filtration rate (r = 0.75, n = 15) 3.
• In patients with normal renal function, 40% of the administered dose is eliminated through the kidney, while in those with impaired renal function, this percentage decreases to 16% and 8% for groups I and II, respectively 3.
• The total apparent ciprofloxacin clearance (CL/f) is related to creatinine clearance (CLCR) by the equation CL/f = 2.83 x CLCR + 21.8 (r = 0.69; P less than 0.001) 4.

Dosage Adjustments in Renal Impairment

• Recommended dosage adjustments in patients with impaired renal function vary between countries, with major adjustments not required until the estimated creatinine clearance is < 30 ml/min/1.73m2 (or when the serum creatinine level is > or = 2 mg/dl) 5.
• In renal failure, either the dose can be reduced or the administration interval can be prolonged in proportion to the reduced ciprofloxacin clearance 6.
• Prolongation of the administration interval may be the preferable dose adjustment method in renal failure with ciprofloxacin 6.
• Patients with CLCR less than 1.2 liters/h per 1.73 m2 should receive two-thirds of the normal daily dose, and the dose interval should not be lengthened 4.

Pharmacokinetics in Critically Ill Patients

• Renal function is a significant covariate on ciprofloxacin clearance in critically ill patients 7.
• A dose of 400 mg every 12 hours may be sufficient to reach the target area under the curve (AUC) in relation to the minimum inhibitory concentration (MIC) (AUC/MIC) > 125 in patients with an estimated glomerular filtration rate (eGFR) < 130 mL/min and an infection caused by a pathogen with an MIC ≤ 0.125 mg/L 7.
• Higher doses than the standard licensed dose may be necessary to obtain target attainment for less susceptible pathogens and patients with high renal clearance 7.