Flunisolide is a synthetic fluorinated corticosteroid with anti-inflammatory and glucocorticoid activity. It is used primarily in inhaled and intranasal pharmaceutical preparations for the management of inflammatory respiratory and nasal conditions.
Flunisolide has the molecular formula C₂₄H₃₁FO₆ and anhydrous molecular weight of 434.51 g/mol. Its CAS number is 3385-03-3. The USP monograph describes Flunisolide as the hemihydrate, with formula C₂₄H₃₁FO₆·½H₂O and molecular weight 443.51 g/mol.
IUPAC Name:
(1S,2S,4R,8S,9S,11S,12S,13R,19S)-19-fluoro-11-hydroxy-8-(2-hydroxyacetyl)-6,6,9,13-tetramethyl-5,7-dioxapentacyclo[10.8.0.0²,⁹.0⁴,⁸.0¹³,¹⁸]icosa-14,17-dien-16-one.
Flunisolide is a corticosteroid used in inhaled and intranasal pharmaceutical products. Its principal pharmacological action is anti-inflammatory activity mediated through glucocorticoid receptors.
Flunisolide activates glucocorticoid receptors and reduces inflammatory processes. Inhaled or intranasal corticosteroid activity reduces inflammatory mediator activity and helps control inflammation in the respiratory or nasal tissues.
Flunisolide has been formulated in products including:
USP also has a separate Flunisolide Nasal Solution monograph describing an aqueous buffered solution containing 90.0%–110.0% of the labeled amount.
| Parameter | Specification |
|---|---|
| Appearance | White to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 97.0%–102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Heavy Metals | NMT 20 ppm |
| pH (1% Solution) | 5.5 – 6.5 |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 1.0% |
| Melting Point | 150°C – 154°C |