Olopatadine
Ophthalmic antiallergics
Ophthalmic antiallergics
An antihistamine eye drop that also steadies mast cells. It relieves the itch of allergic conjunctivitis caused by pollen, dust or animals.
Quick facts
- Group
- Ophthalmic antiallergics
- Target
- Histamine H1 receptor (plus mast cell stabilisation)
- Used for
- Itching of allergic conjunctivitis
- Key effects
- Burning · Blurred vision
- Monitor
- Relief of itching · Eye pain
- ATC
- S01GX09
No doses: the clinician sets them by the current guideline.
Mechanism of action
The figure shows desloratadine, another H1 antihistamine, in the human H1 receptor; olopatadine blocks the same receptor.
Olopatadine blocks histamine H1 receptors in the conjunctiva, so histamine released by mast cells no longer causes itching and redness. It also reduces the release of mediators from conjunctival mast cells, which helps prevent the next wave of symptoms.
- Allergen triggers conjunctival mast cells
- Olopatadine blocks H1 receptors and steadies mast cells
- Less itching and redness
Indications
- Itching of allergic conjunctivitis (pollen, grass, ragweed, animal hair and dander) Conjunctivitis →
Adverse effects
Common
- Burning, stinging or redness
- Blurred vision
- Dry eye or abnormal sensation in the eye
Contraindications
- Hypersensitivity to olopatadine or any component
- Not for contact-lens irritation
Key interactions
- Other eye drops
- Spaced at least 5 minutes apart
What is monitored
- Relief of itching
- Eye pain, worsening redness or vision change
Administration and safety
- Contact lenses come out before the drop and go back in at least 10 minutes later; no lenses while the eye is red.
- The bottle tip should not touch any surface.
- A solution that changes colour or turns cloudy is not used.
- Also exists as a nasal spray; eye and nose products are different.
Pregnancy and breastfeeding
Human data are limited; with little systemic absorption, it is used only if the benefit justifies the risk.
Nursing care
- Confirm the symptom is itching with allergen exposure, not pain or loss of vision.
- Teach drop technique and lens removal.
- Teach to stop and seek review for eye pain, vision change or worsening redness.
Pharmacokinetics
- Absorption
- Acts locally in the eye
Test yourself
Think of the answer, then tap the question to see it.
What are olopatadine's two actions?
H1 receptor blockade and mast cell stabilisation.
What should a contact-lens wearer do?
Remove them before the drop, wait before reinserting, and not wear them while the eye is red.
Which symptoms suggest something other than allergy?
Eye pain, vision change or worsening redness.
Connections
← Back to the class: Ophthalmic antiallergics
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: DailyMed - OLOPATADINE HYDROCHLORIDE solution/ drops (DailyMed (U.S. National Library of Medicine), 2026); Olopatadine Ophthalmic: MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2026); ATCDDD - ATC/DDD Index (WHO Collaborating Centre for Drug Statistics Methodology, 2026); RCSB PDB - 8X64: CryoEM structure of the histamine H1 receptor-BRIL/Anti BRIL Fab complex with desloratadine (RCSB Protein Data Bank, 2026).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.