Olopatadine eye drops are indicated for the treatment of signs and symptoms of allergic conjunctivitis, including itchy, watery, red, and swollen eyes and/or eyelids. It is also used in conditions such as vernal keratoconjunctivitis, vernal keratitis, blepharitis, blepharoconjunctivitis, and giant papillary conjunctivitis.

Olopatadine nasal spray is indicated for the relief of symptoms of seasonal allergic rhinitis in adults and children aged 6 years and older.

Olopatadine tablets are indicated for the treatment of allergic rhinitis (nasal inflammation due to allergens such as pollen and mold spores) and allergic skin conditions. It helps relieve symptoms such as skin rashes, swelling, hives (itchy and painful eruptions), itching, sneezing, runny nose, and nasal congestion.

Olopatadine is an antihistamine that reduces allergy symptoms by blocking the action of histamine in the body. Olopatadine hydrochloride helps relieve sneezing, itching, runny nose, and other allergic nasal symptoms.

Mode of Action: Olopatadine is an anti-allergic agent that works through multiple mechanisms. It stabilizes mast cells (including basophils and conjunctival mast cells) and inhibits the immunologically triggered release of histamine. It also acts as a selective H1 histamine receptor antagonist. By binding to H1 receptors, olopatadine blocks the signaling pathway and reduces the release of inflammatory mediators such as tryptase, prostaglandin D2, TNF-alpha, and other pro-inflammatory cytokines.

Pharmacokinetics:
Absorption: After twice-daily intranasal administration, olopatadine reaches peak plasma concentrations within 30 minutes to 1 hour.

Distribution: It is moderately protein bound (~55% in human serum), and this binding is independent of concentration within 0.1–1000 ng/mL range.

Metabolism: Olopatadine is minimally metabolized. At least six minor metabolites are found in human plasma.

Elimination: The elimination half-life is approximately 8–12 hours. It is primarily excreted through urine.

Eye Drops

• 0.1%: One drop in each affected eye two times per day at an interval of 6 to 8 hours.
• 0.2%: One drop in the affected eye once a day.
• 0.7%: One drop in each affected eye once a day.

Nasal Spray

• Administer Olopatadine Nasal Spray by the intranasal route only.
• Adults and Adolescents 12 years of age and older: Two sprays per nostril twice daily.
• Children 6 to 11 years of age: One spray per nostril twice daily.

Tablet

• Adults: Take 1 tablet (5 mg of the active ingredient) at a time, twice daily, in the morning and before going to bed. The dosage may be adjusted according to the disease, age or symptoms.
• Children 7 years old or over: Take 1 tablet (5 mg) at a time, twice daily, in the morning and before going to bed.
• If you miss a dose, take a dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and follow your regular dosing schedule. You should never take two doses at one time. Do not stop taking this medicine unless your doctor instructs you to do so.

How to use the Nasal Spray

• Shake the bottle gently and remove the dust cover.
• Hold the spray with your forefinger and middle finger on either side of the nozzle and your thumb underneath the bottle. Press down until a fine spray appears. If using for the first time or if you have not used it for a week or more, press the nasal applicator several times until a fine moist comes out from the container.
• Gently blow the nose to clear the nostrils.
• Close one nostril and carefully insert the nasal applicator into the open nostril. Tilt your head forward slightly and keep the spray upright. Breathe in through your nose and while breathing in, press the white-collar of nasal applicator firmly down once to release a spray.
• Breathe out through your mouth.
• Repeat the above steps in the same/other nostril for consecutive doses.

Cleaning: The nasal spray should be cleaned at least once a week. The procedures are as follows:

• Remove the dust cover.
• Gently pull off the nasal applicator.
• Wash the applicator and dust cover in warm water.
• Shake off the excess water and leave to dry in a normal place. Avoid applying additional heat.
• Gently push the applicator back on the top of the bottle and re-fix the dust cover.

Formal drug–drug interaction studies have not been conducted for olopatadine nasal spray. Interactions with hepatic enzyme inhibitors are not expected because olopatadine is primarily eliminated through renal excretion. In addition, clinically significant interactions involving cytochrome P450 enzyme inhibition or plasma protein binding are not anticipated.

This medicine is contraindicated in patients with known hypersensitivity to olopatadine or any component of the formulation. Olopatadine 5 mg tablets are not recommended in patients with allergy to the drug. Patients should inform their physician about existing medical conditions and current medications to ensure safety.

Headache has been reported rarely. Other possible side effects include asthenia, blurred vision, burning or stinging sensation, cold-like symptoms, dry eye, foreign body sensation, eye redness (hyperemia), hypersensitivity reactions, keratitis, eyelid swelling, nausea, pharyngitis, itching, rhinitis, sinusitis, and taste disturbance.

Olopatadine was not found to be teratogenic in animal studies (rats and rabbits). However, adequate and well-controlled studies in pregnant women are not available. It should be used during pregnancy only if clearly needed. It is unknown whether topical ocular use leads to significant systemic absorption or presence in breast milk; therefore, caution is advised during breastfeeding.

Patients should avoid wearing contact lenses when the eyes are red. Olopatadine eye drops should not be used for contact lens–related irritation. Benzalkonium chloride in the formulation may be absorbed by soft contact lenses; therefore, lenses should be removed before use and reinserted at least 10 minutes after application if eyes are not red. Treatment should be stopped if allergic reactions occur. For nasal spray, prime before first use by releasing 5 sprays until a fine mist appears. If not used for more than 7 days, re-prime with 2 sprays. Avoid spraying into the eyes. Patients must be instructed carefully regarding correct usage. Olonex tablets should be taken exactly as prescribed, at the same time daily, and not stopped abruptly without medical advice.

Geriatric Use: No significant differences in safety or effectiveness have been observed between elderly and younger patients.

There is no specific information on olopatadine overdose. However, excessive use of any medication may cause serious effects. In case of suspected overdose, immediate medical attention is required.

Ophthalmic non-steroidal drugs

Store at room temperature, protected from light. The bottle should preferably be used within one month after opening.