Fluorescein Strips in Canada vs the US: Which Route Applies?

Quick facts

• A fluorescein strip is a paper strip impregnated with fluorescein sodium. It is touched to the tear film, then read under cobalt blue light. It stains where the corneal or conjunctival surface is not intact.
• United States: there is no device classification for fluorescein. A search of the FDA device classification database for the term returns a lamp, 21 CFR 878.4580, and nothing else; the drug label database returns fluorescein sodium ophthalmic as a human prescription drug.
• Canada: the same logic applies. An agent instilled into the eye is a drug under the Food and Drug Regulations, and a drug identification number is required before sale.
• The strip beside it goes the other way. The Schirmer tear test strip is a device with a named entry, 21 CFR 886.1800, Class I.
• The class of a non-drug dye carrier is derived in Canada. A device that comes into contact with the surface of the eye is Class II under Rule 2(1) of Schedule 1 to the Medical Devices Regulations.
• The buying test is the DIN and the label, not the strip count in the box.

Two strips of filter paper sit within reach of a slit lamp. One is a device, one is a drug, and the pair is the clearest example of how a regulatory route follows the substance rather than the shape. This article sets out what each strip does, how each country routes the fluorescein version, why the tear test strip diverges from it, what the label has to carry, and how a clinic should stock and record the two lines.

What is a fluorescein strip, and what does it do in the eye?

Fluorescein sodium is a dye. When it reaches a surface that has lost its epithelial layer, it pools in the defect and fluoresces under blue light, which is why a cobalt filter on a slit lamp turns the cornea into a map of its own injuries.

The strip format exists for control. A drop of liquid dye delivers an uncontrolled volume, and a multi-dose bottle raises a contamination question. A strip delivers a controlled amount by touch, which is why it is the format used for routine work.

The three routine uses are:

• Corneal defect assessment. A linear or punctate staining pattern after a foreign-body removal, a scratch or a contact lens problem.
• Tear film assessment. The time taken for the tear film to break up after a blink is read against the pattern of staining.
• Contact lens fitting. The pattern under a rigid lens shows how the lens sits against the cornea.

The paper carries the dye, and that is the only reason the article is complex: the carrier is paper, but the active part is a drug.

Why is a fluorescein strip a drug in the United States and not a device?

Because the device framework answers a question about articles, and the dye is not an article doing a physical job. It is a substance doing a chemical one.

The finding is repeatable in two public databases, which is what makes it worth quoting to a supplier:

• The FDA device classification database, searched for the term, returns an AC-powered fluorescein lamp in Class II under 21 CFR 878.4580. A lamp is a light source with a job. The strip itself does not appear.
• The FDA drug label database returns fluorescein sodium products labelled for ophthalmic use as human prescription drugs with an ophthalmic route, alongside an intravenous presentation of the same active ingredient.

A strip that is saturated with a prescription dye is therefore dispensed on the drug side of the house, and the container carries the drug labelling that goes with it, not a device label.

How do the Canadian and United States pathways differ for the same strip?

Item	Canada	United States
Route for a dye-bearing ophthalmic strip	Drug, under the Food and Drug Regulations	Drug, human prescription, ophthalmic route
Identifier before sale	Drug identification number	Not applicable
Device classification for fluorescein	None	None
Nearest named device entry	None; devices are classified by rule	21 CFR 878.4580, AC-powered fluorescein lamp, Class II
Route for a plain tear test strip with no dye	Device; class derived by rule	21 CFR 886.1800, Schirmer strip, Class I
Class for a non-drug device that contacts the eye surface	Class II under Schedule 1 Rule 2(1)	Not applicable; no eye-contact rule of this shape
Who holds the licence or listing	Manufacturer, importer or distributor	Manufacturer or repackager

Canada reaches the same destination by a different road. The Medical Devices Regulations apply to devices; the Food and Drug Regulations apply to drugs. An agent that is instilled into the eye and that acts by staining tissue is working as a drug, so it takes the drug route and a drug identification number is required before it can be sold.

Canada's device rules do still matter for the carrier, and Rule 2(1) is the reason. Any device that "comes into contact with the surface of the eye" is Class II, unless a subrule moves it. That rule is written for devices, so it does not catch the dye itself; it catches the accessory product that touches the eye without being a drug, which is why a clinic that buys both lines is buying from two different regulatory regimes.

Does a tear test strip follow the same route in Canada and the United States?

No, and the contrast is the useful part. A Schirmer strip is filter paper. It carries no dye, and its job is mechanical: it is inserted under the lower lid and wetted by tears.

21 CFR 886.1800 identifies it precisely: "a device made of filter paper or similar material intended to be inserted under a patient's lower eyelid to stimulate and evaluate formation of tears", and places it in Class I. The exemption in that section is tied to devices of the same materials used before 28 May 1976.

In Canada the paper strip is a device, and the class follows Schedule 1. Because it contacts the surface of the eye, Rule 2(1) sends it to Class II unless a more specific rule applies, and Rule 7(1) catches non-invasive devices that are not otherwise classified at Class I. Which rule governs depends on how the strip is intended to be used, and that is exactly the wording a buyer should expect to see in an intended-use statement rather than infer from a product photograph.

Strip	What it carries	United States route	Canada route
Fluorescein strip	Fluorescein sodium dye	Drug, prescription ophthalmic	Drug, identification number required
Schirmer strip	Filter paper only	21 CFR 886.1800, Class I	Device, class derived by rule
Lissamine green strip	Vital dye	Drug	Drug
Rose bengal strip	Vital dye	Drug	Drug

What does the label have to carry?

For a drug-side product, the label is the specification, and four items should be checked on every delivery:

• The identification number. A Canadian clinic checks the drug identification number. A United States buyer is buying a prescription drug.
• The expiry date and storage line. Fluorescein is light-sensitive and the strip format ages.
• The stated use. A strip labelled for ophthalmic diagnostic staining is a different product from a strip sold for a non-medical use.
• The unit count and single-use statement. A strip is touched to the eye, so the format has to be one use per strip.

For the device-side tear strip, the check is the intended-use statement, the material and the sterility, because Class I status in the United States sits behind the exemption conditions in the section.

Which consumables does a diagnostic eye lane go through?

A diagnostic lane rarely orders one strip line in isolation. The same cycle usually carries dressings, swabs, tape, a warm compress product, gloves, table paper and a surface disinfectant. For practices buying at case level, the wholesale ordering page sets out account and case pricing, and the B2B wholesale collection lists the lines held for institutional buyers. The graphene USB heated eye mask is the warm compress line we hold for lid care routines. Lanes that also run an in-house sterilizer can start with the biological indicator 5-pack trial and read the sterilization monitoring collection for the monitoring lines.

Sources

1. US Food and Drug Administration, openFDA drug label API
2. US Food and Drug Administration, openFDA device classification API
3. 21 CFR 886.1800, Schirmer strip
4. 21 CFR 878.4580, surgical lamps including the AC-powered fluorescein lamp
5. Medical Devices Regulations, SOR/98-282, full text, Schedule 1
6. Health Canada, medical devices
7. FDA device classification database search
8. College of Optometrists of Ontario
9. Opto, Canadian Association of Optometrists eye health library
10. American Academy of Ophthalmology, eye health
11. American Optometric Association, healthy eyes
12. Canadian Ophthalmological Society
13. National Eye Institute, eye health information
14. Public Health Ontario, infectious diseases
15. CCOHS, osh answers
16. World Health Organization, blindness and visual impairment
17. ISO 15004-1:2020, ophthalmic instruments, general requirements
18. Ontario, what OHIP covers
19. Clinical and Laboratory Standards Institute
20. US Department of Labor, OSHA bloodborne pathogens standard, 29 CFR 1910.1030

Related reading

• Eye masks in Canada vs the US: warm compress and dry eye
• Eye clinic consumables: gloves, swabs and tape for optometry
• Comprehensive eye check-up in Canada vs the US: which exam interval
• Eye wash solution in Canada vs the US: which flushing-fluid rules apply

CliniEco Medical supplies eye care, laboratory and clinic consumables of the kind described in this article. Health Canada MDEL #35334. This article is written for clinic, procurement and eye care professionals and is not clinical guidance; staining technique, interpretation and any prescribing decision belong to the treating optometrist or physician.

Frequently Asked Questions

Is a fluorescein strip a medical device in the United States?

No. The FDA device classification database has no entry for fluorescein; the only related entry is an AC-powered fluorescein lamp in Class II under 21 CFR 878.4580. Fluorescein sodium ophthalmic appears in the drug label database as a human prescription drug with an ophthalmic route, so the strip follows the drug framework.

Does Canada route fluorescein strips the same way?

Canada splits the framework the same way: devices are regulated under the Medical Devices Regulations and drugs under the Food and Drug Regulations. A dye that is instilled into the eye acts as a drug, so it needs a drug identification number before sale, and the strip container carries drug labelling rather than a device label.

Why is a Schirmer strip treated differently from a fluorescein strip?

Because it carries no dye. 21 CFR 886.1800 describes the Schirmer strip as filter paper inserted under the lower eyelid to stimulate and evaluate tear formation, and puts it in Class I. The paper does a mechanical job, so it is a device; the dye does a chemical job, so it is a drug.

What class would a non-drug eye-contact device take in Canada?

Class II, under Rule 2(1) of Schedule 1, which sends any invasive device that penetrates a body orifice or comes into contact with the surface of the eye to Class II unless a more specific subrule applies. Devices that do not contact the eye and are not otherwise classified fall to Class I under Rule 7(1).

What should a Canadian clinic check on a fluorescein strip delivery?

The drug identification number, the expiry date, the storage statement and the stated ophthalmic diagnostic use. Fluorescein is light-sensitive, so the storage line and the date are part of the specification rather than paperwork.

Can a clinic substitute one strip format for another?

Only against the labelled use. A tear test strip and a staining strip look similar and do different jobs, and substituting one for the other is use outside the intended purpose. Keep the two lines separated on the shelf and check the label at the point of use.