A relevant choice for corticoid eye drops: solution or suspension?]

The various forms of ophthalmic pharmaceutical presentation of steroids is proliferating on the market: solutions, gels, and suspensions. Suspensions are characterized by particles in solution and require agitation before instillation. This trial studied the impact of agitation on the corticoid concentration of eye drop solutions, gels, and suspensions.Corticosteroid levels in a drop of a dexamethasone solution or suspension or betamethasone suspension or gel were compared using liquid chromatography. These levels were measured after shaking for 5, 10, 30s, and 1 min using a vortex or without shaking.The results of this study show that, whatever shaking time was used, the suspension form seems less suited to instillation of corticosteroids. The suspension did not deliver consistent levels of corticosteroids (mean between 23 and 99%) compared to solutions and gels, which released about 100% of the corticosteroid content in each drop.Physicians, ophthalmologists, and pharmacists should remind the patient of the proper use of these suspensions before instillation. In cases of treatment failure, it is necessary to check the instillation method before questioning patient compliance.