What type of eye drops are recommended for a patient with conjunctivitis (pink eye)?

Eye Drops for Pink Eye (Conjunctivitis)

The type of eye drops needed for pink eye depends entirely on the underlying cause—viral conjunctivitis requires only supportive care with artificial tears and antihistamines, bacterial conjunctivitis may benefit from topical antibiotics (though mild cases are self-limited), and allergic conjunctivitis responds best to topical antihistamines with mast cell-stabilizing activity. 1

Immediate Diagnostic Approach

Before prescribing any eye drops, determine the etiology by assessing:

• Discharge character: Watery discharge suggests viral or allergic causes; mucopurulent discharge with matted eyelids indicates bacterial conjunctivitis 1, 2
• Conjunctival reaction: Follicular pattern on inferior tarsal conjunctiva points to viral; papillary reaction suggests bacterial or allergic 1
• Associated symptoms: Itching is the hallmark of allergic conjunctivitis; preauricular lymphadenopathy suggests viral (especially adenoviral) 1
• Laterality: Viral typically starts unilateral then becomes bilateral; bacterial can be either 1

Treatment Algorithm by Etiology

Viral Conjunctivitis (Most Common in Adults)

Do NOT use antibiotic eye drops—they provide no benefit and may cause toxicity. 1

Recommended eye drops:

• Artificial tears (preservative-free): Use every 2-4 hours for symptomatic relief and to dilute viral particles 1, 2
• Topical antihistamines: For symptomatic relief of irritation 1
• Cold compresses: Refrigerated artificial tears provide additional cooling comfort 3, 2

Critical caveat: Topical corticosteroids should generally be avoided unless managing severe cases with pseudomembranes or subepithelial infiltrates, and only under ophthalmology supervision due to risks of prolonging viral shedding, worsening HSV infections, and causing elevated intraocular pressure 1, 4. If steroids are used, close monitoring with IOP checks and pupillary dilation is mandatory 1.

Bacterial Conjunctivitis (More Common in Children)

Mild cases are self-limited and resolve without treatment in 60% of cases by days 2-5. 5

Recommended approach:

• Moderate to severe cases: Prescribe a 5-7 day course of broad-spectrum topical antibiotic 1
• No single antibiotic is superior to others—choose based on cost and convenience 1, 6, 7
• Common options include: Moxifloxacin 0.5% (one drop three times daily for 7 days) 6 or gatifloxacin 0.5% (one drop every 2 hours while awake on day 1, then 2-4 times daily for days 2-7) 7

Important consideration: Delayed antibiotic prescribing (giving prescription but advising to wait 2-3 days before filling) achieves similar symptom control as immediate prescribing and reduces unnecessary antibiotic use 2. Antibiotics modestly speed resolution—by days 6-10, clinical remission occurs in 64% with antibiotics versus 41% with placebo 5.

Allergic Conjunctivitis

First-line eye drops:

• Topical antihistamines with mast cell-stabilizing activity: Olopatadine or ketotifen are the treatments of choice 3, 1
• Refrigerated artificial tears: Help dilute allergens and provide cooling relief 3

Adjunctive measures:

• Cold compresses 3
• Environmental modifications (wearing sunglasses, avoiding allergens) 3

For refractory cases: A brief 1-2 week course of topical corticosteroids with low side-effect profile may be added, but requires monitoring for IOP elevation and cataract formation 3, 1

Avoid: Chronic use of topical vasoconstrictors (over-the-counter "redness relief" drops) as they cause rebound vasodilation 3

Red Flags Requiring Immediate Ophthalmology Referral

Do not simply prescribe eye drops if any of the following are present:

• Visual loss or decreased vision 1
• Moderate to severe pain 1
• Severe purulent discharge (consider gonococcal conjunctivitis requiring systemic therapy) 1
• Corneal involvement on fluorescein staining 1
• History of herpes simplex virus eye disease 1
• Immunocompromised state 1
• Conjunctival scarring or lack of response to therapy 3

Critical Pitfalls to Avoid

• Never use antibiotics for viral conjunctivitis—they cause unnecessary toxicity without benefit 1
• Never use topical corticosteroids indiscriminately—they can worsen HSV infections, prolong adenoviral shedding, and cause glaucoma/cataracts with prolonged use 1, 4
• Do not miss gonococcal conjunctivitis (marked lid edema, severe purulent discharge)—this requires immediate systemic antibiotics and can cause corneal perforation 1
• Avoid contact lens wear during any infectious conjunctivitis 1
• Do not use preserved eye drops in patients with suspected allergic conjunctivitis, as preservatives can worsen allergic contact dermatitis 8

Patient Education

For infectious conjunctivitis (viral or bacterial):

• Wash hands frequently 3
• Avoid sharing towels and pillows 3
• Avoid close contact with others for 10-14 days from symptom onset 1
• Do not wear contact lenses until infection resolves 1