• Know Your Drops by Color

    As a medical student and intern, you memorized hundreds of medications, drug classes and mechanisms of action. But now you’ve entered a new realm of medication memorization and management: eye drops and cap colors.

    As a new ophthalmology resident, you’ll inevitably get a phone call in the middle of the night asking for a refill of an eye drop. Many times, the only detail the patient may have is the color of the cap.

    The chart below is an introduction to the most common drops you will come across in your first months of residency. Although this is not a complete list of uses or complications, it’s a starting point and may serve as a good reference on those late-night consults.

    In the charts below, the branded name is listed in parentheses.

    Steroid Drops

    (In order from strongest to weakest)

    Drug Lid Color
    Indications Cautions
    Difluprednate 0.05%
    (Durezol)
    Pink Postoperative inflammation

    Iritis
    Causes highest incidence of elevated IOP and cataracts compared with steroid drops below
    Prednisolone acetate 1%
    (PredForte)
    Pink/white Postoperative inflammation

    Iritis
    Can cause elevated IOP and cataracts
    Fluorometholone 0.1%
    (FML)

    Loteprednol 0.5%
    (Lotemax gel)
    Pink/white Ocular surface inflammation/dry eye

    Postoperative inflammation
    Can cause elevated IOP and cataracts, but to a much lesser extent than the two above
    Loteprednol 0.2%
    (Alrex)
    Pink/white Seasonal allergies  

    Dilation Drops

    Drug Lid Color
    Duration Indications Cautions
    Phenylephrine 2.5%, 10%
    (Neosynephrine)
    Red 3 hours Use with tropicamide for adult dilation Avoid 10% in hypertensive crisis, pediatrics and the elderly
    Tropicamide 1%
    (Mydriacil)
    Red 4–6 hours Use with phenylephrine for adult dilation  
    Cyclopentolate 1%, 2% (Cyclogyl) Red 24 hours Cycloplegic refractions  
    Atropine 1% Red 7–10 days Breaks posterior synechiae

    Decreases ache from ocular inflammation

    Fogging for amblyopia treatment
    Avoid in angle-closure glaucoma
    Cyclopentolate 0.2%/Phenylephrine 1% (Cyclomydril) Red 24 hours Cycloplegic refraction, dilated exam in infants (lower concentration may require repeat dosing) Bradycardia, apnea in neonates

    Anesthetic Drops

    Drug Lid Color
    Duration Indications Cautions
    Proparacaine
    (Alcaine)

    Tetracaine

    (Pontocaine)
    White 10–30 min Topical anesthesia

    Breaks down corneal epithelium ulcers

    Speeds absorption of subsequent drops
    Long-term use causes corneal ulcers

    Check corneal sensation before use in setting of ulcers or other corneal pathology
    Benoxinate + Fluorescein
    (Fluress)
    N/A, dropper 10–20 min Applanation tonometry

    Stains defects on corneal/conjunctival surface

    Topical anesthesia
    Not for Seidel tests (use fluorescein paper strips)

    Patients may see yellow when they blow their nose

    Glaucoma Drops

    Drug Lid Color
    Dosing Class Cautions
    Timolol 0.5%
    (Timoptic) + several others
    Yellow QAM or BID Beta blocker Avoid in patients with asthma, COPD, CHF and bradycardia
    Brimonidine 0.1%, 0.15%, 0.2%
    (Alphagan)
    Purple BID-TID Alpha agonist Avoid in patients under 3 years of age

    Avoid in women who are nursing or who are near their delivery date (though it is the only class B glaucoma drop)

    Dorzolamide
    (Trusopt)

    Brinzolamide 1%
    (Azopt)

    Orange TID Carbonic anhydrase inhibitor Avoid in sulfa allergy

    Avoid in sickle cell patients with hyphema (can induce sickling in anterior chamber)

    Patients may complain of bitter or metallic taste

    Bimatoprost 0.01%, 0.03%
    (Lumigan)

    Travoprost 0.004%
    (Travatan Z)

    Latanoprost 0.005%
    (Xalatan)

    Tafluprost 0.0015%
    (Zioptan)
    These drops come in single-use vials, so there is no lid color.

    Teal green QHS Prostaglandin agonist May reactivate herpes simplex virus keratitis

    Darkens hazel irides

    Increases eyelash length, amount

    Conjunctival hyperemia is common

    Avoid in uveitic glaucoma and late pregnancy (may induce labor)
    Dorzolamide 2%/Timolol 0.5%
    (Cosopt)
    White with dark-blue strip or solid dark blue BID Carbonic anhydrase inhibitor + beta blocker  
    Brimonidine 0.2%/Timolol 0.5%
    (Combigan)
    Dark blue BID Alpha agonist + beta blocker  
    Latanoprostene bunod 0.024% Teal green QHS Nitric oxide donating prostaglandin analog  
    Netarsudil 0.02% (Rhopressa) White QHS Rho kinase inhibitor Conjunctival hyperemia is common
    Acetazolamide
    250-mg,
    500-mg extended release
    (Diamox)
    N/A BID-QID Carbonic anhydrase inhibitor Avoid in sulfa allergy

    Avoid in sickle cell patients with hyphema (can induce sickling in anterior chamber)

    Avoid in patients with a history of kidney stones

    Beware with potassium-losing diuretics or digitalis

    Common side effects include peripheral limb tingling/weakness, bad taste with carbonated beverages and diarrhea
    Methazolamide
    25-mg
    (Neptazane)
    N/A BID- TID Carbonic anhydrase inhibitor Same as above, but less severe

    Antibiotic Drops

    Drug Lid Color
    Indications Cautions
    Moxifloxacin
    (Vigamox)

    Gatifloxacin

    (Zymaxid)
    Tan Fourth-generation fluoroquinolone

    Postoperative

    Corneal ulcers
     
    Ofloxacin
    (Ocuflox)
    Tan Third-generation fluoroquinolone

    Postoperative
     
    Erythromycin
    (Emycin)
    N/A,
    ointment/tube
    Macrolide

    Bacterial conjunctivitis

    Sterile cornea defects to prevent infection

    Prevents ophthalmia neonatorum
     
    Bacitracin ointment
    (Bacitracin)
    N/A,
    ointment/tube
    Cationic polypeptide  
    Tobramycin/
    Dexamethasone ointment
    (Tobradex)
    Pink/white, also available as ointment/tube Aminoglycoside

    Gram negatives (Pseudomonas)
     
    Neomycin/
    Polymyxin/
    Dexamethasone ointment (Maxitrol)
    N/A,
    ointment/tube
    Aminoglycoside + cationic polypeptide + strongest topical steroid

    Postoperative

    Common gram positives
    Neomycin is the most common cause of contact dermatitis

    * * *

    Bradley S. Henriksen, MDBradley S. Henriksen, MD, joined the YO Info editorial board in 2022. He is a pediatric ophthalmologist in Provo, UT, who completed his residency and fellowship at Oregon Health Science University, Casey Eye Institute, in Portland, OR.