From the Guidelines
For azithromycin renal dosing, the recommended dose for patients with renal impairment is as follows:
- For patients with creatinine clearance of 30-50 mL/min, no dose adjustment is necessary.
- For patients with creatinine clearance of less than 30 mL/min, a dose of 250 mg once daily is recommended, but this should be used with caution due to limited data 1.
- For patients undergoing hemodialysis, a dose of 250-500 mg once daily is recommended, with the dose given after dialysis on dialysis days 1. It's essential to note that these recommendations are based on limited data, and caution should be exercised when using azithromycin in patients with renal impairment.
- Monitoring of serum drug concentrations should be considered to ensure adequate drug absorption, without excessive accumulation, and to assist in avoiding toxicity 1.
- The medications should be given after hemodialysis on the day of hemodialysis 1.
- Data currently are not available for patients receiving peritoneal dialysis, and until data become available, begin with doses recommended for patients receiving hemodialysis and verify adequacy of dosing using serum concentration monitoring 1.
From the FDA Drug Label
Special PopulationsRenal Insufficiency Azithromycin pharmacokinetics were investigated in 42 adults (21 to 85 years of age) with varying degrees of renal impairment. Following the oral administration of a single 1,000 mg dose of azithromycin, mean Cmax and AUC0-120 increased by 5.1% and 4. 2%, respectively in subjects with mild to moderate renal impairment (GFR 10 to 80 mL/min) compared to subjects with normal renal function (GFR >80 mL/min). The mean Cmax and AUC0-120 increased 61% and 35%, respectively in subjects with severe renal impairment (GFR <10 mL/min) compared to subjects with normal renal function (GFR >80 mL/min). (See DOSAGE AND ADMINISTRATION.)
The appropriate dosing of Azithromycin in patients with impaired renal function is not explicitly stated in the provided text, but it is mentioned that the pharmacokinetics were investigated in adults with varying degrees of renal impairment.
- Mild to moderate renal impairment (GFR 10 to 80 mL/min): No significant changes in dosing are implied.
- Severe renal impairment (GFR <10 mL/min): Increased Cmax and AUC0-120 were observed, but no specific dosing recommendations are provided. It is recommended to consult the DOSAGE AND ADMINISTRATION section for further guidance, as mentioned in the text 2.
From the Research
Azithromycin Dosing in Impaired Renal Function
- The pharmacokinetics of azithromycin in patients with impaired renal function were examined in a study published in 1995 3.
- The study found that the area under the plasma concentration curve, distribution volume, and maximal plasma concentration of azithromycin were not significantly affected by renal insufficiency.
- Therefore, the dosage regimen of azithromycin in patients with renal impairment may be the same as in patients with normal renal function 3.
- However, other studies have highlighted the importance of dose adjustment in patients with renal impairment for other medications, with varying degrees of consistency in dosing recommendations across different sources 4, 5, 6, 7.
- A study published in 2015 found that only 30% of recommended dosing schemes for patients with renal impairment were associated with similar average concentrations as expected in patients with normal renal function 4.
- Another study published in 2014 found that there was a lack of consistency in dosing information across different drug information sources, highlighting the need for an evidence-based approach to drug dosage adjustment in patients with renal impairment 5.
- Studies have also shown that dose adjustment in patients with renal impairment is often neglected, with only 32% of prescription entries requiring dose adjustment being correctly adjusted in one study 6, and 58.9% of prescriptions requiring dosage adjustments being performed in another study 7.