Rohto Cool Eye Drop

Rohto Cool Eye Drop is an ophthalmic solution from the Rohto eye care range, sold in Malaysia through DoctorOnCall as an over-the-counter product that does not require a prescription. It is supplied in a compact plastic dropper bottle intended for topical, repeated self-administration into the eye, and is formulated with a distinctive cooling sensation on application, a signature characteristic of the Rohto Cool line.

The formulation contains several active and functional ingredients, including Menthol, Tetrahydrozoline hydrochloride, Hypromellose, Potassium Chloride, Boric Acid, Zinc Sulfate, and other buffering agents. Tetrahydrozoline hydrochloride belongs to the imidazoline class of topical vasoconstrictor ingredients, Menthol provides the characteristic cooling sensation associated with this product line, Hypromellose is a viscosity-increasing and lubricating agent, and Zinc Sulfate is an astringent ingredient. Together, this places Rohto Cool Eye Drop in a different product class from a plain saline or lubricant-only eye drop, since it contains an active vasoconstrictor ingredient rather than being a simple lubricant.

Because it contains tetrahydrozoline, Rohto Cool Eye Drop is formulated differently from products such as Rohto Dry Aid Eye Drop, which relies on propylene glycol as a lubricant without a vasoconstrictor ingredient. Rohto Cool Eye Drop is supplied by DoctorOnCall in standard bottle sizes as listed on the product page, and, as with any product containing a vasoconstrictor, it is intended for short-term, occasional use strictly according to the instructions printed on the packaging.

Wash your hands thoroughly before use. Check that the solution is clear before each use; if it looks cloudy, discoloured, or contains visible particles, do not use it.

Tilt your head back slightly and gently pull down the lower eyelid to form a small pocket. Hold the bottle tip close to, but not touching, the eye, eyelid, lashes, or any other surface, and instil the recommended number of drops into the lower eyelid pocket.

Close your eyes gently for a moment and blink a few times to spread the drop evenly across the eye. Replace the cap securely straight after use to protect the tip and the remaining solution from contamination.

The usual adult dose is 1 to 2 drops in the affected eye or eyes, up to 4 times a day as needed, or as directed by a pharmacist or doctor. Because this product contains a vasoconstrictor ingredient, it is intended for short-term or occasional use rather than continuous daily use over an extended period.

This product is not recommended for children without first consulting a doctor. If symptoms persist beyond a few days of use, stop using the drop and seek advice from a pharmacist or doctor rather than continuing to apply it.

Use before the expiry date printed on the bottle and carton. Once opened, discard the bottle after the in-use period stated on the packaging or bottle label, as the solution cannot be considered sterile indefinitely once the seal has been broken.

Store Rohto Cool Eye Drop at room temperature, below 30°C, away from direct heat and sunlight, unless the packaging states otherwise. Keep the bottle upright with the cap tightly closed between uses.

Keep out of reach and sight of children at all times, as accidental ingestion of eye drops containing a vasoconstrictor such as tetrahydrozoline can cause serious effects in young children and requires urgent medical attention. Avoid letting the dropper tip touch the eye or any other surface during use.

• Common: Temporary stinging, burning, or a cooling sensation immediately after application, consistent with the menthol content.
• Common: Brief blurring of vision for a few moments after the drop is instilled.
• Common: Mild pupil changes or temporary sensitivity to light in some individuals.
• Serious: Rebound eye redness that becomes worse than before treatment, which can occur with repeated or prolonged use of vasoconstrictor eye drops and needs medical review if it develops.
• Serious: Signs of a more significant reaction such as marked eye pain, irregular heartbeat, palpitations, or a noticeable rise in blood pressure, which require urgent medical attention, as tetrahydrozoline can occasionally be absorbed systemically.

• Diagnosed or suspected narrow-angle glaucoma, as vasoconstrictor eye drops such as this one can raise pressure inside the eye in susceptible individuals.
• Known allergy or hypersensitivity to tetrahydrozoline hydrochloride, menthol, or any other ingredient in this formulation.
• Use in children without first consulting a doctor, due to the risk of more pronounced effects from vasoconstrictor ingredients in younger age groups.
• Continuous, prolonged, everyday use beyond a few days, as this can lead to rebound redness and worsening of eye symptoms once the drop is stopped.
• Use with a solution that appears cloudy, discoloured, or is past its expiry or in-use period.

• People taking monoamine oxidase inhibitor (MAOI) medicines, or who have stopped an MAOI within the past two weeks, should avoid this product or check with a doctor first, as tetrahydrozoline may interact with MAOIs.
• People with high blood pressure, heart disease, an overactive thyroid (hyperthyroidism), or diabetes should check with a doctor or pharmacist before using this product, as tetrahydrozoline’s vasoconstrictor action may not be suitable for everyone with these conditions.
• If using more than one eye drop product, space each one at least 5 to 10 minutes apart so one does not wash out another.
• There are no significant food interactions, as this product is applied topically to the eye rather than swallowed.

• Use this drop only for short periods and avoid continuous daily use beyond what is stated on the packaging.
• Wash and dry your hands before every application to avoid contaminating the bottle tip.
• Keep the tip away from your eye, eyelashes, or fingers during application.
• If you wear contact lenses, remove them before use and wait at least 15 minutes before reinserting, unless advised otherwise.
• Note the date the bottle was first opened so you know when to discard it.
• Store the bottle upright with the cap firmly closed, out of reach of children, between uses.

Precautions: This product contains tetrahydrozoline, a vasoconstrictor ingredient, and should not be used by anyone with diagnosed or suspected narrow-angle glaucoma. It is intended for short-term or occasional use only; using it continuously for more than a few days without medical advice is not recommended, as this can lead to rebound eye redness. People with high blood pressure, heart disease, hyperthyroidism, or diabetes, and those taking MAOI medicines, should check with a doctor or pharmacist before use, and it should not be used in children without medical advice.

When to See a Doctor or Pharmacist: Seek medical advice if eye redness, irritation, or discomfort persists or worsens after a few days of use, or if you notice eye pain, a change in vision, or increasing redness after stopping the drop. Seek urgent medical attention if the product is swallowed, especially by a child, or if you notice signs of a systemic reaction such as an irregular heartbeat, palpitations, or feeling unusually unwell after use.