Why multiple eye drops need a five-minute gap

When you are prescribed two or three drops, it is tempting to put them all in at once and be done. But different drops usually come with instructions to space them out.

Your eye can only hold so much

When you put in a drop, some of it stays on the surface of the eye and some drains away through the tear duct. Adding the next drop straight away can wash the first one out before it has had time to stay put. That is why it helps to leave a gap when you use several drops in a row.

Plenty of clinic handouts say something like 'about five minutes'. The point is less the exact number and more the habit of not putting everything in at once.

Five minutes is harder than it sounds

Before leaving for work or right before bed, five minutes is not short. You put in the first drop, start doing something else, and forget the second one — or you get impatient and put it in immediately.

• Start a timer as soon as the first drop is in
• Give each drug a fixed colour or a fixed place
• Tick off the first one so you don't skip the second

The interval warning in EyeDay

When you log several drops, EyeDay checks the spacing against your recent doses. For people on several drops at once — glaucoma, or the weeks after surgery — that 'you just put one in' check is the useful part.