A member recently raised a query with me in person at a CET event, and she asked that I share my answer with readers in case not everyone had come across it. The query was: how long before the expiry date on a pack of contact lenses may you issue the lenses to a patient?
Firstly, I think you have to establish some facts. The expiry date on the box is a ‘use by’ date not a ‘sell by’ date. Technically, it’s the seal that might fail and thus compromise the safety of the product. The next fact to establish is: for what purpose are the lenses being supplied? Is it a five-lens strip to be used over the following week to check on the fitting and comfort of the lens, or a 90-pair pack to be used as and when the patient wishes?
Immediately, you can see the problem: one answer doesn’t suit all. It would be my view that the ‘use by’ date is checked at the point of issue to ensure that the date will not be exceeded for the expected use, and add a bit. This is not scientific, certainly, but common sense. I know some practitioners say a clear 12 months before the ‘use by’ date when issuing contact lenses, to be doubly sure.
A regular wearer using lenses most days, discarding generally on time, will use a three-month supply in a little over three months, so the ‘use by’ date should be six months beyond the date of supply to satisfy all contingencies. Also, perhaps consider where the patient might store their lenses; cool and dark is best, not in the handbag that sits next to the radiator in the office, as one patient of mine confessed to!
If patients abuse their contact lenses, and many do so regularly, it does not look good when we say: “Don’t do that but it’s ok to use the lenses past their use by date”. Patients generally take your lead; if you take extra trouble with their lenses and care then so will
they. It all comes back to the ‘putting the welfare of the patient before all other considerations’. What is the best action from the patient’s perspective?
There is another problem, which was raised at the CET event, of how to dispose of the out-of-date stock of diagnostic lenses. The official advice is to use the ‘non-hazardous healthcare waste’ route, which involves placing in tiger bags and disposing of as ‘offensive waste’. It was suggested that there is a real danger of such lenses being retrieved from the waste bags and sold on in car boot fairs or down the pub.
Many of those in the audience that night commented that they opened these out-of-date lens packets before discarding, to prevent such sales. It would be nice to think this wasn’t necessary, but sadly I expect it is something we should all do.