How often is Merrem (meropenem) for pyelonephritis?

From the Guidelines

Meropenem (Merrem) for pyelonephritis should be dosed at 1 g t.i.d. This recommendation is based on the most recent guidelines from the European Association of Urology, as outlined in their 2024 guidelines on urological infections 1. The dosing frequency of meropenem for pyelonephritis is every 8 hours, which is a standard practice for this medication. Key points to consider when using meropenem for pyelonephritis include:

• The medication is typically reserved for complicated cases, healthcare-associated infections, or when there is suspected or confirmed resistance to more commonly used antibiotics.
• Meropenem works by inhibiting bacterial cell wall synthesis and is effective against a broad spectrum of gram-positive, gram-negative, and anaerobic bacteria.
• Patients should be monitored for improvement in symptoms such as fever, flank pain, and urinary symptoms, with consideration for stepping down to oral therapy once clinically improved and culture results are available. It's also important to note that dose adjustments are necessary for patients with renal impairment, as meropenem is cleared by the kidneys 1. Overall, meropenem is a valuable option for the treatment of pyelonephritis, particularly in cases where other antibiotics may not be effective.

From the Research

Merrem (Meropenem) for Pyelonephritis

• The frequency of Merrem (meropenem) administration for pyelonephritis can vary based on several factors, including renal function and the severity of the infection 2, 3.
• A study from 1999 found that meropenem was effective in treating severe complicated urinary tract infections, including pyelonephritis, when administered at a dose of 1g every 8 hours for patients with normal renal function, and 1g every 12 hours for patients with impaired renal function (creatinine clearance below 50 ml/min) 2.
• Another study from 2000 highlighted the importance of adjusting meropenem dosages in patients with renal insufficiency, as the drug is primarily excreted unchanged in the urine 3.
• The pharmacokinetics of meropenem have been studied in various patient populations, including those with renal failure and those receiving renal replacement therapy, to determine the optimal dosing regimens 3, 4.
• A phase 3 clinical trial (TANGO I) compared the efficacy and safety of meropenem-vaborbactam to piperacillin-tazobactam in patients with complicated urinary tract infections, including acute pyelonephritis, and found that meropenem-vaborbactam was non-inferior to piperacillin-tazobactam in terms of clinical cure or improvement and microbial eradication 5.
• The dosing frequency of meropenem in this trial was every 8 hours, and the study demonstrated the effectiveness of this regimen in achieving clinical cure or improvement and microbial eradication in patients with complicated urinary tract infections, including acute pyelonephritis 5.

Key Findings

• Meropenem is effective in treating pyelonephritis, especially when administered at appropriate doses and frequencies based on renal function 2, 3, 5.
• The drug's pharmacokinetics and pharmacodynamics support its use in patients with complicated urinary tract infections, including those with renal impairment 3, 4.
• Meropenem-vaborbactam has been shown to be non-inferior to piperacillin-tazobactam in treating complicated urinary tract infections, including acute pyelonephritis 5.