Published: 2023-03-20

The reasons for itching, the pathophysiology of dry eyes, what causes conjunctivitis, and what an "allergic salute" is being covered in the question-and-answer part.


We spoke with Arthur Benjamin on what might seem to be normal topics for an ophthalmologist, but it amazed me; maybe you will be amazed, as well. 

What do people commonly complain about, other than loss of vision?

 One of the most common complaints is itchy eyes.  Although many people specifically come for farsightedness, nearsightedness, eye fatigue, or glaucoma, 90% also complain of itchy eyes.

What causes itchiness?

 It depends on the person.  They often ask for eyedrops to relieve the itching, or say, “I have allergies, so give me eyedrops,” but itching isn’t necessarily related to allergies.  The eyes could be scratched, bloodshot, or a foreign body might be causing that sensation, and ophthalmologists must figure out the cause.  Most frequently, it’s dryness.  Tears, which the eyes could not survive without, consist of three layers:  oily, aqueous, and mucin.  If any of these are defective, the problems begin.

What are the functions of these layers?

 The oily layer prevents the evaporation of tears from the surface of the eye.  The aqueous layer flushes out foreign bodies, such as dust, dirt, and allergens.  And the mucin layer helps the tears to spread evenly.  It is important to determine which of the layers is defective, resulting in dryness,

Is there a common cause for these malfunctions?

 There are different causes: blepharitis, conjunctivitis…

I know there will be more of these rhyming words, but I must interrupt; we have never talked about conjunctivitis before.  What is conjunctivitis?

 It is an inflammation of the conjunctiva, which is the mucous membrane covering the eye.  I don’t want to complicate our discussion, so I’ll just say that the cause could be traumatic, bacterial, or viral.  In the latter case, when someone sneezes or coughs, the airborne makes its way into the eyes or mouth.

So if you’re socializing with someone who has the flu, don’t hesitate to wear glasses?

 Or a mask.  Conjunctivitis has infectious and non-infectious periods, and is seasonal.  In countries with relatively distinct seasons, it usually occurs in the fall or spring.  In California, where something is always blooming, dying, and regrowing, allergies flourish year-round.  And on top of that, it can accumulate.

But allergies aren’t only in the eyes…

 Right.  There might be rhinitis, nasopharyngeal itching, clogged ears, etc., but people frequently come to the ophthalmologist with allergic conjunctivitis.  When we are having a dry season, allergies are less common, but during my beloved rainy season, allergies increase.  Everything that has settled in the desert – plant pollen, insect particles, and fungal spores – is brought to life and blown into the city.  Therefore, we invite all that are affected in for an examination.  You could of course take a lozenge or use drops, but the most important thing is to find the cause, because there is no drop that can replace the immune process.  It produces different allergy-related symptoms.  For example, the “allergic salute” is common in children, where they try to relieve the itching and impaired breathing by wiping their nose with their hand from the bottom up.  An experienced ophthalmologist needs to see them immediately.

 How do we determine these causes?

 Allergens evoke a reaction.  In our office, we offer a special test which determines how you react to the 60 most common allergens.  Cats, dogs, palm trees, all varieties of herbs, olive trees, down pillows, cockroaches…

Like the large, flying beauties we have here?

 Not necessarily.  Many people are allergic to cockroach legs, antennae, and horns.  There are also allergies to dust mites.

I didn’t know, by the way, that people could be allergic to dogs.  Cats are a common allergy.  What’s the difference?

 (to be continued)