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When Can Anti-Allergy Eye Drops Help and When It Can Be More Serious! 

There are many eye drops available, many widely obtainable without even a recommendation from an Eye Care/Heath Care Professional. Some have clinical trial evidence behind them and are authorised by the Medicines and Healthcare products Regulatory Agency (MHRA), others use some of ‘natures’ ingredients and while they may help they not have been subject to the standards of proof medicines have. Most eye allergy is relatively benign but unpleasant, however some forms do have the potential to be sight-threatening! The only sure way of knowing is to be examined by an Eye Care Professional.

Ocular Allergies

First let’s look at ocular allergies and how they may be managed. To help us, let’s start with basics, what is an allergy? We can consider it an inappropriate inflammatory reaction to foreign substances by the body’s immune system, whereas it’s appropriate for the immune system to react to fight off parasites, bacteria or viruses for instance, an inappropriate reaction to usually harmless substances like pollen, molds, dust mites etc manifests itself as allergy. The substances that trigger allergy are called allergens.

Immunoglobulin E (IgE) is an antibody that all of us have in small amounts. Allergic individuals, however, generally produce IgE in larger quantities. During a sensitisation period an allergen causes the body to overproduce IgE which coats cells such as mast cells and basophils, these contain various mediators, such as histamine. These coated cells are now primed, ready to react to all subsequent exposures to the allergen, this leads cells to the release of the allergic mediators mentioned above (Type 1 reaction within minutes). These chemicals cause typical allergic symptoms, such as localized swelling, inflammation, itching, and mucus production.

Master Cell

Histamine is the main mediator of type I allergic reactions. In ocular tissue, histamine release from mast cells induces itching, tearing, swelling of the conjunctiva and eyelids and blood vessel dilation. Type IV hypersensitivity is a cell-mediated process involving T-cells, cytokines, and macrophage activation. The response peaks at 48 to 72 hours (called “delayed” hypersensitivity) and results in tissue damage.

Typical symptoms include sudden onset of ocular itching (the symptom of true itching is highly indicative of an allergy component), irritation, burning sensation and watering.

Mast cell stabilisers

Pharmaceutical agents called mast cell stabilisers inhibit the release of histamine and therefor its effects, sodium cromoglycate 2% is such an agent, was the first mast cell stabiliser and the one most used by patients with ocular allergy, mainly because not only is it available as a prescription and pharmacy medication but it is now widely available from many sources without medical supervision in preserved and single-dose non-preserved forms. However, it can take several days before its use starts to relieve symptoms, in fact it is advocated sodium cromoglycate is ideally used several days before the antigen is encountered. Systemic side-effects are rare but not unknown, topical side-effects are normally mild and transient.


Anti-histamines inhibit the activity of histamine and its signalling pathways between cells. Both systemic and topical anti-histamines can be divided into first generation where the potential for systemic side-effects is greater, such as sedation, dry mouth, dry eye, blurred vision, constipation and urine retention. These effects can happen with topical application but are less likely than if taken orally. Second generation anti-histamines tend not to produce these effects as much.

They will tend to have a more rapid effect in relieving symptoms than the mast cell stabilisers, all though generally well tolerated, as with all eye-drop medication, topical side-effects can occur, ranging from burning, eye redness and stinging through lid swelling to eye surface damage.

Decongesting, avoiding, cooling and flushing!

Many eye drops with the names that include or imply a ‘dazzling’, ‘brightening’ ‘sparkling’ or ‘redness relieving’ (grouped under the title of ocular decongestants) effect contain agents such as naphazoline which constrict conjunctival blood vessels, relieving eye redness, tearing and irritation. The effect is normally rapid, however ocular side-effects such as mild pupil dilation and an increase in intraocular pressure may occur. Systemic side-effects have been reported, amongst them being changes in heart rate and blood pressure.
Other simple, readily available, methods of relieving symptoms of ocular allergy instead, or as well as medication are; to avoid contact with the source of the offending allergen be it a cat, grass/tree pollens etc this is a basic strategy but amazingly effective! Cool applications (aka cold compresses, a term I try to avoid as occasionally patients will go home to compress their eyes!), this too will have a vasoconstriction effect and relieve itching. Dry eye drops if used several times per day will have a flushing effect, diluting and/or washing out allergens and inflammatory mediators, having read previous articles of mine on topical eye therapy you will know I would recommend they are non-preserved.

So you can see that what might appear to be a simple problem, with a quick and easy remedy is more complex and the answers are more nuanced. If at all possible, to help with eye allergy problems that don’t manifest themselves significantly in other parts of the body, we would always recommend specific eye drops, used in a specific way, perhaps alongside other direct methods of reducing symptoms, so a more comprehensive approach than ‘redness relieving’ drops alone. We will even show you how to reduce the possibility of adverse side-effects from the medications, remember these can occur in prescription and non-prescription eye drops!

Contact Lenses

Although it is not possible to be 'allergic' in the true meaning of the word to contact lenses, it is possible for patient's to find certain lenses more 'bio-compatible' than others. It is certainly possible imune system responses can be trigered by contact lens care products or depoits on the lenses. A Contact Lens Practitioner is by far the best person to determine the cause and answer to contact lens related problems.  

Sight threatening?

At the beginning of this article we mentioned the posiiblity that the eye's allergic reaction can be sight-threatening. Because of the potential for vision loss, it is critical that the form of ocular allergy is correctly identified. Keratoconus and cataract formation are common in certain eye allergies which can also cause corneal ulceration. It is also thought that persistent eye rubbing results in an increased risk of retinal detachment. This correct identification of the specifc form of eye allergy cannot be be done by a GP or pharmacist, only by a Eye Care Professional using a bio-micropscope to examine the eye.


Allergic response under superior lid
Allergic response under superior lid


Longer term complication of untreated eye allergy
Longer term complication of untreated eye allergy


By far the best way for us to help is through a consultation, be it remotely or even better face-to-face.

If you would like to contact us for non-urgent eye care discussions related to eye allergy, dry eyes or contact lenses you can  by email:

  • Andrew D Price (Nantwich, Widnes or general enquiries) This email address is being protected from spambots. You need JavaScript enabled to view it.  
  • Elizabeth Ralph (East Midlands and South Yorkshire) This email address is being protected from spambots. You need JavaScript enabled to view it. 
  • Vanessa Uden (Surrey, Hants, Berks) This email address is being protected from spambots. You need JavaScript enabled to view it. 
  • Mr Ganeshbabu Mahalingam (West Yorkshire) This email address is being protected from spambots. You need JavaScript enabled to view it.

Personal portfolios can be found here: 



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Dry/Watery Eye FAQs

Eye makeup and skin care used in and around the eyes is a potential source of irritation, inflammation, infection, allergy and possibly adverse permanant changes to eye health. As just one example out of many aspects of eye cosmetics Amy Gallant Sullivan, Creator of 'Èyes Are The Story' highlights eyelash extensions; "eyelash extensions aren’t always pretty, lash extensions can cause irritation, conjunctivitis, keratitis, and even severe allergic reactions. False eyelashes can promote the risk of bacterial & fungal infection. Eyelash extensions can even cause eyelash loss! Watch the video for more information on lash extension.


You will find the Eyes Are The Story web site here.

Kathyrn Chidwick BSc(Hons) Ophthalmic Dispensing, in a recent article in Re:View the ABDO College journal, discussed the possible contamination and infections from ocular cosmetics. Her critical research analysis found studies that revealed high contamination of ocular cosmetic products being used by patients with potential sight-threatning bacteria and fungi. It is strongly advisable for ocular cosmetics not to be shared or used past their expiry date. 

The same research analysis found studies showing eye liner can destabilise the tear film and block the vital meibomian glands in the eye lid. Many skin-care products contain retinoids, these may cause or excerbate meibomian gland dysfunction. 

Alllergic reactions to the multitude of chemicals found in ocular cosmetics have been known for many years, even leading to a dermatitis condition on the eye lids, from the ocular cosmetics themselves, or hair products. 

The complete article can be found in the December 2021 issue of Re:View  .


Always apply makeup outside the lash line and apply mascara from the tips rather than the roots of the lashes, preferably to the top lashes only.

Never apply eye makeup over the oil glands that line the very edge of your upper and lower lids, just inside the eyelash line. These are the glands that secrete oils to keep the eye lubricated. If you need to use an eye drop, apply it 15-30 minutes before putting on your makeup.


It is a must to remove makeup before bed. Sleeping with eye makeup on can lead to clogging of the oil producing glands and eye infections. Try a gel based product that is oil and paraben free. Avoid getting the makeup remover into the eyes as this may irritate them further.
Avoid mineral oil, sodium lauryl sulfate, and diazolidinyl urea. While they work well to remove makeup, they are known to cause irritation to the eyes.
A gentle lid scrub with baby shampoo on a clean cotton pad or soft cloth or a store bought lid scrub can help remove excess makeup and unclog the eye’s oil glands.

Makeup Hygiene

Keeping makeup applicators clean is critical to keep infection at bay. Make sure to sharpen your makeup pencils before application to remove the top coat of bacteria. Also, wash makeup brushes as well as using a brush cover to keep them clean. Avoid using store samples, but if you must make sure to use a fresh applicator.
Do not use the same applicator on different parts of the face. For example, do not use the same pencil on your lips and your eyes.
Avoid sharing makeup with anyone else and using makeup past its expiration date. As a rule of thumb, dispose of your eye makeup every three to six months. You can keep a marker in your makeup kit to note the date the makeup was opened.
Do not use any type of eye makeup if you have an eye infection and see your optometrist right away. If you do develop an infection, throw away all your eye makeup and buy a new set to start with after your optometrist OKs you wearing it again.
Always wash your hands before applying makeup and avoid using saliva to assist in putting your makeup on as this could lead to an eye infection.

Makeup Type

The tiny particles in glitter and powder based shadows and foundation can get into and aggravate the eyes. Instead sparingly use cream shadows, highlighters and foundations.
Use a thickening mascara instead of lash-lengthening or waterproof ones as they are less likely to flake and get into the eyes.
Stick with hypoallergenic brands to avoid excess irritation. Avoid makeup with arsenic, beryllium, cadmium, carmine, lead, nickel, selenium, and thallium.

Find Alternatives

A plastic eyelash curler is a great alternative to mascara. (The metal in regular eyelash curlers can cause irritation and dryness around the eye).
You might also get away with less eyelid makeup if you concentrate on your eyebrows instead.

If you suffer from severe and chronic dry eye and are intolerant of eye makeup try highlighting other aspects of you face, such as your lips and cheeks, which allows you to highlight your natural beauty without ever touching your eyes.

Eyelash extensions

These have grown in popularity due to beauty trends favoring the appearance of more robust eyelashes and eyebrows. Eyelash extensions are synthetic fibers (e.g. polyester) that are applied on the natural lashes using glue that may contain chemicals such as formaldehyde, lead, and benzoic acid.  Allergic reactions to eyelash glue can be serious as well as associated complications including keratoconjunctivits, contact dermatis and blepharitis, conjunctival and corneal erosion, subconjunctival hemorrhage. To prevent complications arising from eyelash extensions, both the patients and the beauty industry should learn the potential complications of the procedure and the ingredients of the glue and lash removers should be strictly regulated and monitored.


Yes, it is possible. Many general health conditions have a role in dry eye and/or blepharitis. At your Dry Eye Assessment we will want to know about your general health and health conditions/treatments you have had in the past. We believe it is simply not possible to address your dry eye condition and best help you without knowing this information. Just as one example, rheumatoid arthritis or other types of inflammatory disease are a risk factor in dry eye disease, so if that is the case we would want to manage it specifically, another good reason why self-treatment with self-selected eye drops is not advised.

Yes, it is possible. Many general and eye medications and the conditions they are taken for can exacerbate the general condition called dry eye. At your Dry Eye Assessment we will want to know your medications, food supplements and ask about your diet, do you eat oily fish for instance. We believe it is simply not possible to address your dry eye condition and best help you without knowing this information. Importantly we very rarely advocate a medication change but rather work with your medication prescriber to manage your dry eye condition, certainly you should not change medication in any way without consulting your doctor or pharmacist.

On an allied point there are available specific dry eye food supplements with evidence of effectiveness available, but these are contra-indicated if you are taking certain medications or other food supplements, we will advise you at your Dry Eye Assessments. 

As in the ‘hot flannels’ question, this advice, although well meaning, is not based on any evidence of its effectiveness. In fact there is evidence that it can adversely affect vital glands on the eye surface that contribute to good quality tears. It also has a detergent effect, which actually beaks up the tear film. Its use has never been proposed by the manufacturers of such a product, and recently a well-known global producer of ‘baby shampoo’ officially wrote to an UK ophthalmologist strongly supporting his advice against its use. 


If this was the question in 1975, perhaps so, if only because we didn’t understand the complexity of the eye lids or the tears then and we had nothing better. This approach was neither safe (risk of it being too hot and/or very unhygienic) or effective (the required heat is not maintained for nowhere near long enough). In 2020, with our much better understanding of the ocular surface, lids and tears we know much better. Heat application alone is not usually sufficient to help one of the types of dry eye (the type of dry eye needs to identified correctly) most Eye Care Professionals, who understand dry eye/blepharitis would not advocate their use.

Yes, most glaucoma drops have preservatives within them to protect against contamination. Very often the continued application of these very necessary drops, with their preservatives, to the eye can cause eye surface inflammation and irritation.
Many of the same age group of patients using glaucoma drops are predisposed to dry eye, these two factors (preservatives and dry eye) often mean the eye is not comfortable.
The answer is NOT to stop using the glaucoma drops, they are vital, it may well be, after a specific Dry Eye Assessment, the dry eye and effects of the glaucoma drops can be managed better, leading to the eyes being more comfortable and, evidence has shown, the glaucoma drops being more effective.

Although a few specific dry eye drops have very sophisticated formulations, even they don’t have ability to stay on the eye’s surface for many hours. Most dry eye drops, with more basic components, will have only have an effect for one or two hours.
The answer, in many cases, following a specific Dry Eye Assessment and diagnosis (there are different types of dry eye) is to treat the eye’s surface in addition to the use of very particular drops. Once the particular cause is identified in the exam, targeted therapy can be advised, sometimes aided by in-practice treatment. The very good news is that this approach gives me, and more importantly, my patients a 95% success rate!