Logo

OpiCalc

FavoritesSpecialtiesDrugsGuidelinesMost Used

Quick Access

Favorites
Most Used

All Specialties

OpiCalc Logo
Clinical CalculatorsDrugsGuidelines
SpecsDrugsGuides
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
OpiCalc Logo

OpiCalc

Easy, fast, and private medical tools for clinicians. Always free.

No Login Required
Ready for the Bedside

Resources

About UsEditorial PolicyMedical DisclaimerPrivacy PolicyTerms of UseCookie Policy

Support

Contact Us

Clinical Notice:OpiCalc is not a substitute for professional clinical judgment. Always verify dosages and guidelines.

OpiCalc © 2018-2026

•

All Rights Reserved

Registry Hub
Ophthalmic Antiallergic Agent/Over-the-counter

PATADAY TWICE DAILY RELIEF

PATADAY TWICE DAILY RELIEF

Clinical safety rating

caution

Comprehensive clinical and safety monograph for PATADAY TWICE DAILY RELIEF (PATADAY TWICE DAILY RELIEF).


Mechanism of Action

Pataday (olopatadine) is a selective histamine H1 receptor antagonist and mast cell stabilizer. It inhibits the release of histamine and other inflammatory mediators from mast cells, reducing allergic conjunctivitis symptoms.

What the body does with it

MetabolismOlopatadine undergoes minimal hepatic metabolism. Systemic absorption is low after ocular administration; the small absorbed fraction is metabolized by CYP3A4 and other CYP450 enzymes.
ExcretionOlopatadine is predominantly eliminated via renal excretion, with approximately 60-70% of the dose recovered as unchanged drug in urine. The remaining 30-40% is eliminated as metabolites (including N-demethylated and N-oxide derivatives) primarily via urine, with minor fecal excretion (<5%).
Half-lifeThe terminal elimination half-life of olopatadine is approximately 8-12 hours in healthy adults, supporting twice-daily dosing for sustained therapeutic effect.
Protein bindingOlopatadine is approximately 55% bound to plasma proteins, primarily albumin.
Volume of DistributionThe volume of distribution (Vd) of olopatadine is approximately 1.3 L/kg, indicating extensive distribution into tissues beyond plasma volume.
BioavailabilityBioavailability via ocular route: Systemic absorption is minimal; however, following topical ocular administration, the systemic bioavailability is approximately 0.5-1% due to low absorption through the conjunctiva and nasolacrimal duct.
Onset of ActionOcular administration: Onset of action occurs within 30 minutes, with peak effect observed at 2 hours post-dose.
Duration of ActionDuration of action is approximately 8-12 hours following a single ocular dose. Twice daily dosing maintains symptom relief over 24 hours.
Molecular Weight373.88

Classification & Brands

Dosing & administration

1 drop in each affected eye twice daily (approximately every 6-8 hours)

Dosage formSOLUTION/DROPS
Renal impairmentNo dosage adjustment required for any degree of renal impairment. No specific GFR-based recommendations provided by manufacturer.
Liver impairmentNo dosage adjustment required for any degree of hepatic impairment. No specific Child-Pugh based recommendations provided by manufacturer.
Pediatric useChildren 2 years and older: 1 drop in each affected eye twice daily. Safety and efficacy in children under 2 years have not been established.
Geriatric useNo specific dosage adjustment required; geriatric patients should use the same dose as younger adults. Elderly may be more susceptible to local adverse effects; monitor for excessive tearing, conjunctival irritation, or dry eye symptoms.

Use during pregnancy

1st trimesterNo adequate studies in pregnant women. Use only if potential benefit justifies potential risk to fetus.
2nd trimesterNo adequate studies in pregnant women. Use only if potential benefit justifies potential risk to fetus.
3rd trimesterNo adequate studies in pregnant women. Use only if potential benefit justifies potential risk to fetus.

Clinical note

Comprehensive clinical and safety monograph for PATADAY TWICE DAILY RELIEF (PATADAY TWICE DAILY RELIEF).

Placental transferNot studied; low systemic absorption with topical ocular use suggests minimal placental transfer.
BreastfeedingOlopatadine is excreted in human milk following oral administration; however, topical ocular use likely results in negligible systemic exposure. Caution is advised when administered to a nursing woman.
Lactation RatingL3 (Moderately Safe)
Teratogenic RiskNo evidence of human teratogenicity. Animal studies show no malformations at clinically relevant doses. Risk cannot be ruled out; use only if clearly needed.
Fetal MonitoringNo specific monitoring required. Routine obstetric care.
Fertility EffectsNo human data. Animal studies show no impairment of fertility.

Warnings & precautions

■ FDA Black Box Warning

None

Side Effect Profile

Common EffectsEye pain Eye irritation Abnormal eye sensation Eye discomfort Sleepiness Weakness Dryness in mouth
Serious Effects

Absolute Contraindications

Hypersensitivity to olopatadine or any component of the formulationPrimary angle-closure glaucoma (relative, but absolute if untreated)

Clinical Precautions

PrecautionsNot for injection, Patients should not wear contact lenses if eyes are red, May cause transient burning or stinging, Contains benzalkonium chloride which may be absorbed by soft contact lenses
Food/DietaryNo known food interactions. Avoid rubbing eyes which may worsen symptoms.

Clinical Tips & Counseling

Clinical PearlsPataday Twice Daily Relief contains olopatadine 0.1%, an ophthalmic mast cell stabilizer and antihistamine. Use for prevention of ocular itching in allergic conjunctivitis. Advise patients to wait 10 minutes after administration before inserting contact lenses. Monitor for transient stinging or blurred vision. Not for treatment of contact lens-related irritation.
Patient AdviceUse exactly as prescribed: one drop in each affected eye twice daily (every 6-8 hours). · Wash hands before instilling drops. Do not touch the dropper tip to any surface. · Remove contact lenses before use; wait at least 10 minutes before reinserting. · Do not use if solution changes color or becomes cloudy. · Common side effects include mild stinging or burning upon instillation, which usually resolves. · Avoid driving or operating machinery immediately after use if vision is blurred.

PATADAY TWICE DAILY RELIEF Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

PATADAY ONCE DAILY RELIEF

External sources

DailyMed (NIH) PubMed OpenFDA