Eye drop colors are something that has always confused beginning ophthalmology residents. The eye drop bottle colors have been standardized, and you’ll almost always seen the same color for the same drop. Yes, there are sometimes exceptions (especially with generic manufacturers).
We’ve tabulated for you the most important classes of drops in an easy way.
 | Dilating drops – Red Phenylephrine, tropicamide, atropine, cyclopentolate, cyclomydril |
 | Combination drops with timolol – Blue Dorzolamide-timolol (Cosopt), brimonidine-timolol (Combigan) |
 | Alpha agonist – Purple Brominidine (Alphagan) |
 | Prostaglandin analogue – Turquoise Latanoprost (Xalatan), travoprost (Travatan), bimatoprost (Lumigan) |
 | Beta blockers – Yellow Timolol (Timoptic), levobunolol (Betagan) Betaxolol (Betoptic) – light blue top |
 | Carbonic anhydrase inhibitors – Orange Dorzolamide (Trusopt), brinzolamide (Azopt) |
 | Antibiotics – Tan Ofloxacin (Ocuflox), ciprofloxacin (Ciloxan), moxifloxacin (Vigamox, Moxeza), gatifloxacin (Zymar, Zymaxid), besifloxacin (Besivance) |
  | Steroid – Pink or White Prednisolone acetate (Pred Forte/Pred Mild), fluoromethalone (FML), rimexolone (Vexol), loteprednol (Lotemax), difluprednate (Durezol) |
 | Topical NSAID – Gray Ketorolac (acular, acuvail), diclofenac (Voltaren) |
| Topical anesthetics or steroids – White Proparacaine, tetracaine Generic medications, over-the-counter medications |
The AAO worked with the FDA to select the color combinations, which most pharmaceutical companies follow. See the article:
http://www.aao.org/about/policies/color-codes-topical-ocular-medications
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