The Manufacturer's Recommended Dilution for Intravenous Phenytoin and the Challenge of Preparing Single-Dose...

Intravenous (IV) infusion is often utilized when continuous and controlled drug delivery is necessary, such as during surgery or in the treatment of chronic diseases. This method offers numerous advantages, including immediate drug action, precise control over dosage, and bypassing the first-pass metabolism.
The one-compartment model for IV infusion uses mathematical equations to describe the rate of change in drug quantity in the body. At steady-state or infusion equilibrium, the drug input...

In pharmacokinetics, the elimination rate of a drug following a capacity-limited model is primarily controlled by two parameters: Vmax and KM. These parameters are crucial in how the drug behaves inside the body after administration.
Following the administration of a single intravenous (IV) bolus injection, we can determine the concentration of the drug in the plasma at any given time. This calculation is achieved using a specific equation that integrates the values of Vmax and KM.
We can also...

The administration of drugs via parenteral routes allows for direct drug introduction into the systemic circulation, resulting in high bioavailability because the medication bypasses the harsh conditions of the gastrointestinal tract and hepatic metabolism.
The intravenous route (IV) of drug administration can be further categorized into two types. The bolus injection administers the entire dose rapidly, while an intravenous infusion slowly delivers smaller doses steadily.
The IV route is often...

The one-compartment model is a pharmacokinetic tool that models the body as a single, uniform compartment, facilitating the understanding of drug distribution and elimination. This model is particularly beneficial for intravenous (IV) bolus administration, where the drug rapidly circulates throughout the body.
The drug's presence in the body is defined by an equation representing the difference between the rates of drug entry and exit. Key parameters—elimination rate constant,...

In patients with renal impairment, drugs undergo significant changes in their pharmacokinetics, which require dosage adjustments to ensure safe and effective therapy.
Reduced renal clearance and elimination rate are common outcomes of renal impairment. These alterations lead to a prolonged elimination half-life and an altered apparent volume of distribution for drugs. As a result, dosage adjustments are typically necessary to maintain optimal drug levels in the body.
However, dosage adjustments...

The two-compartment model for intravenous (IV) bolus administration illustrates drug distribution in the body, subdividing it into central and peripheral compartments. This model operates on the concept of two-compartment kinetics. The drug's plasma concentration shows a bi-exponential decline following IV bolus administration, signaling the presence of two disposition processes: distribution and elimination.
The disparity between drug input and the sum of drug transfer rates between...