A simple formula for individualising ceftazidime dosage administered by continuous infusion in patients with

Eric Dailly1, Anne Brun, Marie-France Kergueris

  • 1Laboratoire de Pharmacologie Clinique, Hôtel Dieu, 9 Quai Moncousu, 44093 Nantes Cedex, France. eric.dailly@chu-nantes.fr

A formula is proposed for individualising ceftazidime dosage administered by continuous infusion in patients with haematological malignancies. Sixty patients were retrospectively randomised into Group A (n=30) to establish the formula and Group B (n=30) to evaluate this formula. Individual ceftazidime clearances were estimated from the ratio between the rate of infusion and plasma concentration at steady state. In Group A, ceftazidime clearance was significantly correlated with creatinine clearance. From this result, a formula (rate of infusion (g/day)=0.00133x[creatinine clearance (mL/min)]x[target concentration at steady state (mg/L)]) is proposed. This formula provided consistent estimations of ceftazidime plasma concentrations in Group B and should help clinicians to define the optimum ceftazidime dosage, particularly in patients with disturbed renal function.

Related Concept Videos

Determination of Multiple Dosing Parameters: Steady-State, Minimum and Maximum Concentrations01:15

Determination of Multiple Dosing Parameters: Steady-State, Minimum and Maximum Concentrations

Gentamicin, an aminoglycoside antibiotic, is commonly administered via intermittent intravenous infusion to treat severe infections. An intermittent one-hour infusion of gentamicin, administered at eight-hour intervals, allows for precise control of plasma drug concentrations, minimizing toxicity while ensuring therapeutic efficacy. Pharmacokinetic principles govern the dynamics of plasma concentrations and can be mathematically described using specific equations.The plasma drug concentration...
IV Infusion to Oral Dosing: Conversion Methods01:28

IV Infusion to Oral Dosing: Conversion Methods

The development of extended-release formulations has facilitated the transition from intravenous to oral medication, offering a more convenient and patient-friendly approach to drug administration. This transition, however, requires careful management to ensure that therapeutic drug levels are maintained, preserving efficacy and avoiding adverse effects. Understanding pharmacokinetic principles and dosage calculations is critical during this process.Pharmacokinetics of the...
Drug Accumulation During Multiple Dosing: Intermittent IV Infusions01:24

Drug Accumulation During Multiple Dosing: Intermittent IV Infusions

Intermittent intravenous (IV) infusion is a method of drug administration where medications are delivered over short infusion periods followed by intervals of no drug delivery. This approach helps to prevent sustained high drug concentrations in the bloodstream, reducing the risk of adverse effects associated with prolonged exposure. Unlike continuous infusion, steady-state concentrations may not be achieved during a single dosing cycle but can be reached through repeated...
Drug Dosing in Renal Diseases: Dose Adjustments Based on Drug Clearance and Elimination Rate Constant01:25

Drug Dosing in Renal Diseases: Dose Adjustments Based on Drug Clearance and Elimination Rate Constant

In patients with renal disease, dosage adjustments are necessary to maintain therapeutic plasma drug concentrations and prevent toxicity or subtherapeutic exposure. Renal impairment alters drug pharmacokinetics, especially in conditions like uremia, where changes such as prolonged elimination half-life and altered apparent volume of distribution can significantly affect drug disposition. These changes require careful modification of the dosing regimen to achieve the desired clinical...
Dosage Interval and Administration Route: Determination Methods01:19

Dosage Interval and Administration Route: Determination Methods

A medication’s effectiveness largely depends on its appropriate dosage and the route of administration. Dosage ensures that a sufficient drug concentration is maintained in the bloodstream to elicit the desired therapeutic effect without causing toxicity. The route of administration affects the drug's bioavailability, rate of absorption, and onset of action, which are crucial for achieving optimal therapeutic outcomes. Drug dosage calculations are critical to tailoring therapy to individual...
Determination of Multiple Dosing Parameters: Loading and Maintenance Doses01:25

Determination of Multiple Dosing Parameters: Loading and Maintenance Doses

A loading dose is an essential pharmacological strategy to rapidly achieve the target plasma drug concentration necessary for an immediate therapeutic effect. This approach is especially critical for drugs characterized by slow absorption or extended half-lives, where delaying therapeutic plasma levels could compromise treatment outcomes. By administering a loading dose, clinicians ensure a prompt onset of drug action, even for agents with complex pharmacokinetic profiles.Achieving steady-state...