Preservatives in ophthalmic formulations and the urgent need for preservative-free formulation

Abstract

Topical treatment of ocular diseases is mainly through eye drops. One of the short outcomes of eye drops is using preservatives, particularly for chronic diseases such as glaucoma and dry eye syndrome. Preservatives are chemical compounds that must be incorporated into an eye drop to preserve sterility during storage and use. Their chronic use may cause side effects to the eye, such as irritation, allergy, tear film instability, conjunctival inflammation, sub-conjunctival fibrosis and corneal surface impairment. Ophthalmologists and formulation scientists are moving towards preservative-free formulations. Strategies to manufacture preservative-free formulations are either through changing the container type of formulation or converting it into a solid dosage form. Preservative-free formulations were superior to traditional eye drops by minimizing side effects experienced by the patient. Keywords: preservative-free formulation, chemical substance, growth