Solubility

The maximum amount of a substance that can dissolve in a given solvent at a specified temperature and pH, typically expressed in mg/mL for pharmaceutical applications. Aqueous solubility is a critical determinant of oral bioavailability, as a drug must dissolve in gastrointestinal fluids before absorption. The Biopharmaceutics Classification System (BCS) categorizes drugs based on solubility and permeability to guide formulation strategy.

أمثلة

• BCS Class I (high solubility, high permeability): metoprolol — rapid and complete absorption
• BCS Class II (low solubility, high permeability): itraconazole — formulation-dependent bioavailability
• BCS Class IV (low solubility, low permeability): furosemide — variable oral absorption (10-100%)