What is a major disadvantage of using ophthalmic medicinal ointment?

Using ophthalmic medicinal ointments presents a significant downside in that they can cause temporary blurring of vision upon application. Ointments generally have a thicker consistency compared to eye drops, which can lead to a film forming over the surface of the eye. This film can obscure vision until it wears off or is washed away, making it less desirable for individuals needing clear vision immediately after administration, such as those who drive or operate machinery.

While some patients might experience tearing or redness as side effects, these are often not as immediately impactful on vision as the blurriness caused by the ointment's application. Additionally, specific ointments may not necessarily lose effectiveness over time if stored properly and are used within their expiration dates. Therefore, the blurred vision caused by ointments is a clear and immediate disadvantage that can affect daily activities for the patient.