Enhancing Irbesartan Bioavailability via Solid Dispersion

Hypertension is a prevalent condition, especially in those over 50, and can lead to severe cardiovascular complications. Irbesartan, an angiotensin II receptor blocker (ARB), is commonly used to manage hypertension, but its low aqueous solubility (1 μg/ml) limits its bioavailability. This study aimed to improve Irbesartan's solubility through solid dispersions using carriers like β-cyclodextrin, HPMC K4M, PEG4000, and Gelatin. β-cyclodextrin showed the greatest enhancement in solubility, as confirmed by phase solubility studies. Characterization through DSC and SEM indicated the drug's transformation from crystalline to amorphous form, improving dissolution. FTIR studies confirmed no interaction between the drug and carriers. In vitro dissolution tests revealed that β-cyclodextrin (1:9) formulations significantly increased the dissolution rate compared to pure Irbesartan and other carriers. Thus, using β-cyclodextrin in solid dispersions effectively enhances Irbesartan's solubility and therapeutic potential in treating hypertension.