TOC  | ID  

Conjunctivitis  “Red eye”


The term conjunctivitis refers to an inflammation of the conjunctiva resulting from a variety of causes, including allergies and bacterial, viral, and chlamydial infections.

  • Allergic conjunctivitis
  • Bacterial conjunctivitis
  • Viral conjunctivitis
  • Chlamydial conjunctivitis
    Nongonococcal conjunctivitis (except for LGV):
    RX: Azithromycin 1 g PO × 1 or Doxycycline 100 mg PO bid for 7 days.  Alternatives: Erythromycin base 500 mg PO qid for 7 days or Ofloxacin 300 mg PO bid for 7 days or Levofloxacin 500 mg PO qd for 7 days
  • Traumatic conjunctivitis

* Cultures are useful if not successfully treated with antibiotic medications; initial culture is usually not necessary.

  • Acute glaucoma
  • Corneal lesions
  • Acute iritis
  • Episcleritis
  • Scleritis
  • Uveitis
  • Canalicular obstruction

Common Red Eye emergencies can be rapidly diagnosed by asking 3 important questions:

  1. Was physical or chemical trauma involved with the red eye?
  2. Did the patient have previous intraocular surgery (cataract, glaucoma, retinal detachment, LASIK surgeries)?
  3. Does the patient use or sleep overnight in their soft contact lenses - corneal ulcer?


Treatment for Non-emergent Red Eye "Conjunctivitis"
  1. Topical Anesthetics: as Ketorolac (Acular) eye drop
  2. Topical Antibiotics:
    levofloxacin, ofloxin, ciprofloxacin ophthalmic solution one or two drops q2–4h
    * Gentamicin, Tobramycin, & Neomycin are not the preferred choice of antibiotics
    because of possible irritation to the cornea and conjunctiva when used for more than 7-10 days.
  3. Topical Steroids
    Dexamethasone & prednisolone should never be prescribed to patients with unknown etiology.


Allergic Conjunctivitis

Patients with allergic conjunctivitis present with itching of the eyes, accompanied by tearing and a burning sensation. The reaction is usually bilateral, although unilateral conjunctivitis may occur in a patient who has had direct hand-to-eye contact with an allergen such as dog or cat dander.

The periocular tissues are usually swollen and reddened. The conjunctiva is injected, with mild to moderate chemosis, and there is a ropy mucous discharge in the tear film.

Differential Diagnosis of Allergic Conjunctivitis

  1. Infectious conjunctivitis (viral or bacterial).
    Patients with infectious conjunctivitis complain of matting of the eyelids, with a clear to mucopurulent ocular discharge. The conjunctiva is deeply red, and although a burning sensation is common, itching is not as profound as in allergic conjunctivitis.
  2. Vernal conjunctivitis,
    which may also be confused with allergic conjunctivitis, is a severe, bilateral recurrent condition of the eye often occurring in the spring. It is marked by intense pruritus and a typical cobblestone appearance of the upper eyelid.

Treatment of Allergic Conjunctivitis

Drug treatment for allergic conjunctivitis typically begins with a topical over-the-counter antihistamine-decongestant combination such as antazoline-naphazoline (Vasocon-A) or pheniramine-naphazoline (Naphcon-A). The next line of therapy would include a selective H1 receptor antihistamine, a category that includes ketotifen (Zaditor), epinastine (Elestat), levocabastine (Livostin), azelastine (Optivar), and olopatadine (Patanol).  Ketotifen, epinastine, and olopatadine also have mast cell-stabilizing properties.



• Warm compresses if infective conjunctivitis

• Cold compresses in irritative or allergic conjunctivitis


Antibiotic drops (e.g., levofloxacin, ofloxin, ciprofloxacin ophthalmic solution one or two drops q2–4h)
   Gentamicin, Tobramycin, & Neomycin are not the preferred choice of antibiotics because of possible irritation to the cornea and conjunctiva when used for more than 7-10 days.

• Topical anesthetics:  Ketorolac (Acular)  1 gtt qid

Caution: be careful with corticosteroid  (Dexamethasone or Prednisolone) treatment and avoid unless sure of diagnosis; corticosteroids can exacerbate infections


• Depends on the cause

• If allergic, nonsteroidals such as Voltaren (diclofenac) ophthalmic solution, mast cell stabilizers such as Elestat (epinastine), Alocril (nedocromil), Patanol (olopatadine), Zaditor  (ketotifen) are useful

• If infections, antibiotic drops (see Acute General Rx)

• Dry eyes need artificial tears, ristasis, lacrameal duct plugs when indicated


• Red eyes are not just conjunctivitis when there is significant pain or loss of sight. However, it is usually safe to treat pain-free eyes and the normal seeing red eye with lid hygene and topical treatment.

• Beware of patients wearing soft contact lenses and of babies and the elderly.

• Do not use steroids indiscriminately; use only when the diagnosis is certain.

REF: Ferri: Ferri's Clinical Advisor: Instant Diagnosis and Treatment, 8th ed., 2006


To ophthalmologist if symptoms refractory to initial treatment