Treatment of Adult Conjunctivitis (Pink Eye)
Most adult conjunctivitis is viral and self-limited, requiring only supportive care with cold compresses and artificial tears—antibiotics should be reserved for bacterial cases with purulent discharge or specific high-risk scenarios. 1
Diagnostic Approach
The first critical step is determining the etiology, as this drives treatment:
Viral Conjunctivitis (Most Common)
- Clinical features: Watery discharge, follicular reaction in inferior fornix, often bilateral, burning/gritty sensation
- Associated findings: May have preauricular lymphadenopathy, recent upper respiratory infection
- Natural history: Self-limited, resolves in 1-2 weeks without treatment 2
Bacterial Conjunctivitis
- Clinical features: Purulent discharge, mattering/adherence of eyelids on waking, lack of itching, no prior history of conjunctivitis 2
- Natural history: Most uncomplicated cases resolve in 1-2 weeks even without treatment 2
Allergic Conjunctivitis
- Clinical features: Bilateral itching (most consistent sign), watery discharge, chemosis, papillary reaction 1
- Associated factors: Seasonal pattern, environmental allergens 1
Treatment Algorithm
For Viral Conjunctivitis
- No antibiotic treatment indicated 3, 2
- Supportive care only:
- Cold compresses
- Artificial tears
- Patient education on contagiousness (avoid sharing towels, frequent handwashing)
- Exception: If dendritic lesions are seen on fluorescein staining, this indicates herpes simplex keratitis—treat with topical trifluridine and refer to ophthalmology immediately 4
For Bacterial Conjunctivitis
Observation without antibiotics is appropriate for uncomplicated cases 3, but topical antibiotics can shorten duration and allow earlier return to work 2.
If treating with antibiotics:
- Broad-spectrum topical fluoroquinolones (e.g., besifloxacin) are effective 5
- Typical duration: 5-7 days
- Critical red flags requiring immediate ophthalmology referral:
- Contact lens wearer (risk of Pseudomonas keratitis—always treat and refer) 6
- Corneal involvement (infiltrate, ulcer)
- Severe purulent discharge with marked lid edema
For Sexually Transmitted Infections
Gonococcal conjunctivitis:
- Marked lid edema, severe purulent discharge, rapid onset
- Requires systemic AND topical antibiotics 1
- Immediate ophthalmology referral (risk of corneal perforation)
- Systemic ceftriaxone 1g IM single dose
Chlamydial (inclusion) conjunctivitis:
- Follicular conjunctivitis, follicles on bulbar conjunctiva and semilunar fold
- Requires systemic treatment 1, 7:
- Azithromycin 1g single dose OR
- Doxycycline 100mg twice daily for 10 days
- Both regimens equally effective (92-96% eradication) 7
- Treat sexual partners
For Allergic Conjunctivitis
- First-line: Topical antihistamines or dual-acting agents (antihistamine + mast cell stabilizer) 3, 8
- Adjunctive: Cold compresses, artificial tears, allergen avoidance 3
- Systemic antihistamines can be added for severe cases 2
Critical Pitfalls to Avoid
Never use topical corticosteroids empirically without ruling out herpes simplex keratitis—this can cause corneal perforation and permanent vision loss 4
Do not prescribe antibiotics for clear viral conjunctivitis—this increases antibiotic resistance without benefit and adds unnecessary cost 2, 9
Always examine contact lens wearers for corneal ulcers—they require antibiotics covering Pseudomonas and ophthalmology evaluation 6
Recognize hyperacute purulent conjunctivitis (gonococcal)—this is an ophthalmologic emergency requiring same-day referral due to risk of corneal perforation 1
If symptoms persist beyond 2 weeks or worsen, refer to ophthalmology to rule out other diagnoses 4
When to Refer Immediately
- Any corneal involvement (opacity, infiltrate, ulcer)
- Hyperacute purulent conjunctivitis
- Contact lens wearer
- Vision changes
- Severe pain (suggests more than simple conjunctivitis)
- Dendritic lesions on fluorescein staining
- Failure to improve after 2 weeks of appropriate treatment