Part 1: A Look Back – The Pre-Single-Use Era

Prior to the development of snap-off vials, all multi-dose over-the-counter (OTC) eye drops were required to contain preservatives. These additives were essential to minimise bacterial contamination once the bottle was opened, as patients typically continued using them for months — sometimes even years.

While outer packaging may state “discard 90 days after opening”, realistically, how many users retain the box, let alone make note of the date they first broke the seal? Even medical professionals are often guilty of neglecting this instruction.

Unsurprisingly, expired and long-opened eye drops are still in regular use — frequently without visible labels or identifiable batch information. Clinicians routinely encounter patients complaining about ineffectiveness, only to produce a bottle so worn that the branding is nearly erased.

Part 2: The Modern Shift – Rise of the Single-Use Vial

The introduction of preservative-free eye drops in snap-top, single-use vials marked a significant improvement in ocular medication hygiene. These vials are intended for immediate, one-time use and disposal.

In practice, however, each vial often contains more than one dose — sufficient for up to two or three applications depending on technique and dexterity. As a result, many users are tempted to recap and reuse.

⚠️ Important Safety Note:
Recapping a single-use vial is strongly discouraged. Once opened, sterility cannot be guaranteed, and the residual liquid becomes susceptible to microbial contamination. Reintroducing this fluid to the ocular surface can result in serious infections, including corneal ulcers, potential vision loss, or even loss of the eye.

If you suffer from serious ocular surface disorders — such as Stevens-Johnson syndrome, graft-versus-host disease, or limbal stem cell deficiency — you must consult your ophthalmologist before considering any form of recapping.

Part 3: Risk Management – If You Do Recap, Do It Safely

For those who choose to extend vial use despite clinical advice, there are ways to reduce (though not eliminate) the risks:

✅ Tip 1: Cap at an Angle to Indicate “Opened”

Replacing the cap at a slant makes it instantly recognisable as an opened vial. This practice avoids accidental use of multiple open vials or re-opening a fresh one unnecessarily.

✅ Tip 2: Discard All Opened Vials Every Evening

Open vials should never be used beyond 12 hours. Adopt a strict routine of disposing of all opened units at the end of the day. If you’re using Tip 1, there should only be one active vial per product at any time.

Rule of thumb: If in doubt, throw it out.

✅ Tip 3: Dedicated Vial for Scleral Lens Filling

Mark vials used solely for filling scleral lenses with a permanent marker. These vials must not come into direct contact with your eyes.

✅ Tip 4: Use a Clean Container for Transport

A small, empty prescription bottle can act as a hygienic container for a recapped vial. It’s ideal for carrying drops to work or travel, keeping the vial upright and reducing the chance of contamination.

✅ Tip 5: Avoid Storing Drops in Unsuitable Places

Do not store vials:

• In trouser pockets (risk of crushing or warming)
• Inside vehicles, especially in summer
• Loose in handbags, briefcases or backpacks (unless using a protective container as described in Tip 4)

✅ Tip 6: Invest in a Vial Holder

Several commercial vial holders are available online. Circular designs are often more practical, as they separate each unit clearly, making the “angled-cap” vial easier to spot and reducing cross-contamination.

Industry Anecdote: The Restasis Example

During the original regulatory approval process for Restasis (a prescription eye drop), concerns were raised regarding the volume per single-use vial, fearing it would tempt patients to reuse. While the manufacturer provided sufficient justification, they also distributed branded vial holders to clinicians — clearly anticipating patient recapping.

This prompted a warning from the FDA, which reaffirmed that single-use products must not be promoted or supported in ways that encourage multiple usage.

Conclusion: Practicality vs. Protocol

Recapping single-use vials is not recommended and carries measurable risks. However, manufacturers and clinicians alike recognise the practical realities faced by patients — especially given the high cost of many preservative-free formulations.

A forward-looking solution lies in the adoption of multi-dose, preservative-free delivery systems, which combine sterility with convenience, eliminating the need for single-use recapping altogether.

Would you like this version adapted for video narration, social media posts, or filling equipment marketing copy (e.g. for promoting single-dose filling machinery)? I’d be happy to tailor it further.