Start with a free account for 3 free CME credits. Already a subscriber? Sign in.

Allergic Conjunctivitis

Mizuho Morrison, DO, Matthieu DeClerck, MD, and Andy Barnett, MD
00:00
30:34

No me gusta!

The flash player was unable to start. If you have a flash blocker then try unblocking the flash content - it should be visible below.

Allergic conjunctivitis is a common cause of eye discomfort and erythema. While these patients may have impressive symptoms they can almost always be effectively managed in urgent care.

Pearls:

  • Itchiness is the hallmark of allergic conjunctivitis. 

  • Allergic conjunctivitis is typically bilateral if part of a constellation of seasonal/environmental allergies, but can be unilateral if related to a specific exposure (e.g. pet dander). 

  • Chemosis and cobblestoning of the bulbar conjunctivae are strongly suggestive of allergic etiology. 

  • Nasal glucocorticoids and topical antihistamine eye drops are the mainstays of therapy. 

  • Steroid eye drops should not be used because of the possibility of many significant adverse reactions.

  • Encourage patients to stop rubbing their eyes and use lubricating drops instead.

 

  • The primary distinguishing feature of allergic conjunctivitis is itching.  

    • Allergic conjunctivitis, like all allergic phenomena, is histamine mediated.

    • Histamine causes itching as well as vasodilation, swelling, etc. 

  • Patients may also complain of discomfort and/or a gritty foreign body sensation.

  • Allergic conjunctivitis is most often bilateral when related to seasonal allergies, but can be unilateral if the affected eye was topically exposed to the allergen when the eye was rubbed. 

    • Unilateral allergic conjunctivitis is often related to touching the eye after exposure to pet dander. 

    • Preservative agents in eye drops and contact lens solutions can be a common cause of bilateral contact allergic conjunctivitis. 

  • Physical exam:

    • Visual acuity should be near normal for isolated allergic conjunctivitis. 

      • Visual acuity should be corrected to normal with the use of a pinhole test if the impairment is related to a superficial etiology. 

    • Discharge is generally clear or can be straw-colored and crusty after waking.

    • A fluorescein exam is recommended to exclude abrasion/foreign body if symptoms are unilateral.  

    • The conjunctival injection is generally diffuse  – similar to infectious etiologies.

    • Cobblestoning of the bulbar conjunctiva with lid eversion is pathognomonic for allergic conjunctivitis.  

    • Swelling of the eyelids is a common feature of allergic conjunctivitis. 

      • “Allergic shiners” can also be seen from burst capillaries related to frequent eye rubbing.

    • Chemosis is a common and often frightening exam finding for patients, which, though dramatic in appearance, is not dangerous. 

  • Treatment Basics:

    • Encourage patients to stop touching/rubbing their eyes. 

      • If they need to touch their eyes, washing their hands beforehand is important.

    • Contact lens wearers should stop wearing contacts while suffering symptoms of allergic conjunctivitis. 

    • Using refrigerated, non-medicated, lubricating drops hourly can significantly reduce symptoms. 

  • Pharmacotherapy:

    • Nasal glucocorticoids (e.g. Flonase) can be helpful especially if there are accompanying symptoms of allergic rhinitis. 

    • Topical antihistamines are preferred over systemic/oral options.

      • Ketotifen (OTC)

      • Olopatadine (OTC) is an excellent option because of day dosing.

      • Azelastine is available by prescription, for patients requesting an Rx. 

    • Naphazoline-Pheniramine (Naphcon-A - OTC) is a combination of antihistamine & vasoconstrictor which can reduce discomfort from chemosis.

      • Vasoconstrictors are best for immediate relief of abrupt symptoms.

      • Vasoconstrictors are not recommended for more than rare dosing for severe symptoms (e.g. no more than for one week). 

    • Topical glucocorticoid eye drops are not recommended as they can increase intraocular pressure and cause corneal clouding.

    • Cromolyn is an option and is safe in pregnancy, but relief takes days-weeks.

  • Topical antihistamines are safe in children 3 years and older although oral antihistamines (e.g. Cetirizine, Diphenhydramine) may be easier to administer for practical reasons. 

 

References:

  1. Rathi V, et al. Allergic conjunctivitis. Community Eye Health. 2017;30(99):S7-S10.PMID: 29849438

To join the conversation, you need to subscribe.

Sign up today for full access to all episodes and to join the conversation.

To download files, you need to subscribe.

Sign up today for full access to all episodes.
Hippo Urgent Care Written Summary July 2021 7 MB - PDF

To earn CME for this chapter, you need to subscribe.

Sign up today for full access to all episodes and earn CME.

0.25 Free AMA PRA Category 1 Credits™ certified by Hippo (2021)

  1. Complete Quiz
  2. Complete Evaluation
  3. Print Certificate

3.25 AMA PRA Category 1 Credits™ certified by Hippo (2021)

  1. Complete Quiz
  2. Complete Evaluation
  3. Print Certificate