In a pharmacokinetic study comparing flunisolide nasal solution (flunisolide nasal spray .025%) (29 mcg per spray) with flunisolide nasal solution (flunisolide nasal spray .025%) (25 mcg per spray), the original formulation, the two formulations were not bioequivalent. The total absorption of flunisolide nasal solution (29 mcg per spray) was 25% less than that of flunisolide nasal solution (25 mcg per spray), and the peak plasma concentration was 30% lower. The clinical significance of these differences is likely to be small, particularly since clinical efficacy is attributable to a local effect on nasal mucosa (see Pharmacodynamics ).
Mometasone furoate increased chromosomal aberrations in an in vitro Chinese hamster ovary-cell assay, but did not increase chromosomal aberrations in an in vitro Chinese hamster lung cell assay. Mometasone furoate was not mutagenic in the Ames test or mouse- lymphoma assay, and was not clastogenic in an in vivo mouse micronucleus assay and a rat bone marrow chromosomal aberration assay or a mouse male germ -cell chromosomal aberration assay. Mometasone furoate also did not induce unscheduled DNA synthesis in vivo in rat hepatocytes.