Provide a valuable resource to your clients or customers by linking to this resource page. Just place the following link on your website.
The washout phenomenon in eyewear and ocular health refers to the accidental removal of a medicated eye drop by the subsequent application of another drop. If a patient applies two different types of drops too quickly, the second liquid can wash the first medication out of the eye before it has a chance to be absorbed.
read more about washout phenomenon ...Glaucoma patients often use multiple drops:
To prevent the washout phenomenon, eye care professionals recommend waiting at least 5 minutes between different types of eye drops. This allows the first drop to penetrate the ocular surface and be absorbed into the eye's tissues before the next liquid is introduced.
Yes. If you use a medicated drop and then immediately follow it with a contact lens rewetting drop, you will wash out the medicine. Always apply the medicated drop first and wait the full 5 minutes before using your lens lubricants.
During eye surgery, doctors use the washout phenomenon intentionally to clear blood or debris from the anterior chamber. However, for a patient at home, it is a primary cause of treatment failure in chronic eye disease management.
You should wait at least 5 minutes. This gives the first drop enough time to settle into your eye so it is not washed away by the second drop.
Usually, the most important medication should go in first. If you have a liquid drop and a thick gel, always put the liquid in first and the gel last.
They want to make sure you are getting the full dose of your medicine. If you rush your drops, you are likely only getting about half of the treatment you need.
1. Washout Period in Clinical Trials. EyeWiki. https://eyewiki.org/Clinical_Trials_in_Ophthalmology. Accessed February 9, 2026.
2. Understanding the Washout Phenomenon in Glaucoma Medication. American Academy of Ophthalmology. https://www.aao.org/eye-health/diseases/glaucoma-treatment. Accessed February 9, 2026.
3. Clinical Contact Lens Practice. Bennett ES, Weissman BA. Lippincott Williams & Wilkins; 2015.
4. StatPearls. Ocular Pharmacology and Drug Delivery. https://www.ncbi.nlm.nih.gov/books/NBK549900/. Accessed February 9, 2026.
5. Realini T. The effect of drug washout on intraocular pressure. Journal of Ocular Pharmacology and Therapeutics. https://pubmed.ncbi.nlm.nih.gov/21434712/. Accessed February 9, 2026.