Prednisolone disposition in obese men.

Area of Science:

• Pharmacology
• Endocrinology
• Obesity Research

Background:

• Obesity is linked to hormonal imbalances and complicates drug dosing based on body weight.
• Accurate prednisolone dosing in obese patients requires understanding its pharmacokinetic alterations.

Purpose of the Study:

• To investigate the disposition and kinetics of prednisolone in obese versus normal-weight males.
• To determine how ideal body weight (IBW) and total body weight (TBW) influence prednisolone pharmacokinetics.

Main Methods:

• Administered intravenous prednisolone (33 mg) to eight obese and four normal male subjects.
• Measured steroid concentrations using High-Performance Liquid Chromatography (HPLC).
• Analyzed pharmacokinetic parameters in relation to IBW and TBW.

Main Results:

• Obese subjects showed a 20% greater volume of distribution (Vss) for total prednisolone.
• Both total and free prednisolone clearance (Cl) were elevated in obese individuals.
• Free prednisolone Cl strongly correlated with the degree of obesity (TBW/IBW ratio).

Conclusions:

• Prednisolone distribution is influenced by both ideal and total body weight, with limited uptake by adipose tissue.
• Increased free prednisolone clearance in obesity is partially offset by adrenal gland hypersensitivity.
• Weight-proportional prednisolone dosage adjustments in obesity should primarily consider total body weight (TBW).