Rohto Z!

Rohto Z! — The Strong-Cooling Classic, 12 mL

Overview

Rohto Z! is the bottle people mean when they say Japanese eye drops "wake you up". The cooling is the strongest Rohto puts in a consumer product and it is genuinely uncomfortable for some people the first time. Underneath it sits a conventional six-active formula: tetrahydrozoline for redness, neostigmine for focus, zinc sulfate as an astringent, chlorpheniramine for itching, and vitamin B6 with potassium L-aspartate for tissue metabolism. It is worth being clear that the cold is sensation, not medicine — the actives would do the same work in a bottle that felt like nothing at all.

This is a licensed Japanese over-the-counter medicine, not a cosmetic eye product. Everything the manufacturer is allowed to say about it — the indications, the dose, the active ingredients and their percentages — is fixed by the Japanese approval and reproduced here as published. We do not add claims of our own.

Approved indications in Japan: eye fatigue; prevention of eye disease (after swimming, or when dust or sweat enters the eye); ophthalmia caused by ultraviolet or other light (such as snow blindness); discomfort when wearing hard contact lenses; conjunctival congestion; itching of the eyes; blepharitis (inflamed eyelid rims); blurring of vision (as when there is excessive eye mucus).

See the rest of our Japanese eye drops, or the eye-health supplements we ship alongside them.

Key Benefits

• The strongest cooling sensation Rohto sells to consumers — the reason this bottle has a following
• Six actives covering three separate complaints: strain, redness and itching
• Tetrahydrozoline at 0.05% for visible redness in the white of the eye
• Zinc sulfate as an astringent, which is uncommon in the milder Japanese drops
• No chondroitin and no other animal-derived ingredient
• Compact 12 mL bottle with Rohto's free-angle nozzle, which works upside down

Product Details

Brand	Rohto (ロート製薬)
Country of origin	Japan
Product type	Eye drops (ophthalmic solution)
Regulatory class (Japan)	Class 2 OTC medicine (第2類医薬品) — a licensed non-prescription medicine, not a cosmetic
Volume	12 mL
Format	Multi-dose plastic dropper bottle in a printed carton with the Japanese package insert
Contact lenses	Not for use with soft lenses
JAN code	4987241150175
Sold by	Tsujimoto Market, Kobe, Japan

Who Is This For?

• People who want the sharp wake-up feeling and already know they like it
• Anyone dealing with strain, redness and itch at once rather than a single symptom
• Commuters and drivers who use drops as a mid-day reset
• Anyone who wants a formula with no animal-derived ingredient
• Not for you if you wear soft lenses, dislike menthol, have dry eye, or are buying drops for a child — this is an adult-strength cooling formula

How to Use

1. Wash your hands and remove soft contact lenses. Hard lenses may stay in.
2. Tilt your head back. The free-angle nozzle dispenses at any angle, so you do not have to lie down.
3. Instil one to three drops without touching the eye with the nozzle.
4. Close the eye and stay still for about thirty seconds — the cold peaks immediately and eases within a minute.
5. Blot the overflow, cap the bottle, and wait at least ten minutes before putting soft lenses back in.

Frequency: One to three drops, five to six times a day.

Full Ingredients

Active ingredients

• Tetrahydrozoline hydrochloride 0.05% — reduces congestion in the white of the eye
• Neostigmine methylsulfate 0.003% — acts on focus accommodation
• Zinc sulfate hydrate 0.05% — astringent action against inflammation
• Chlorpheniramine maleate 0.03% — antihistamine, for itching
• Vitamin B6 (pyridoxine hydrochloride) 0.1% — tissue metabolism
• Potassium L-aspartate 1% — supports cellular respiration in the eye

Excipients

The excipient list, including the menthol and borneol that produce the cooling, is printed on the Japanese carton. Rohto publishes the six actives above; we do not reproduce an excipient list we have not verified against the box. Ask us for a photo of the panel before ordering if you need it.

Ingredient list as declared by the manufacturer. Formulations are occasionally revised, so always read the list printed on the package you receive.

Cautions

• This is a medicine, not a cosmetic. Personal import of over-the-counter medicines is restricted or prohibited in some countries, and several actives used in Japanese eye drops are prescription-only elsewhere. Check your national rules before ordering — customs may hold or destroy a parcel we cannot get back.
• Do not use while wearing soft contact lenses. This formula is preserved with benzalkonium chloride, which soft lens material absorbs and holds against the cornea. Remove soft lenses first and wait at least 10–15 minutes before putting them back in.
• Read the Japanese package insert supplied with the product. If you cannot read it, ask us for a translation before you use the drops.
• Consult a doctor or pharmacist before use if you are under medical treatment, are pregnant or breastfeeding, have ever had an allergic reaction to a medicine, or have glaucoma.
• Stop using the drops and see a doctor if redness, itching, swelling, pain or blurred vision appear or get worse, or if symptoms have not improved after about two weeks of use.
• Do not use the product after the expiry date printed on the carton, and discard it within the period the insert states after opening.
• Do not let the dropper tip touch the eye, eyelid or lashes, and do not share the bottle with anyone else.
• Keep out of reach of children. Store away from direct sunlight and high temperatures.

Package Contents

One bottle of 12 mL ophthalmic solution in its Japanese retail carton, with the manufacturer's package insert in Japanese. Nothing is repackaged or decanted.

Shipping & Store Notes

• Ships directly from Japan
• Processing time: 2–6 business days
• Tracking number provided after dispatch
• Import duties and taxes may apply depending on destination country
• Opened cosmetics cannot be returned for hygiene and safety reasons

Authenticity Guarantee

Every product at Tsujimoto Market is sourced directly from Japan and verified for authenticity. We never sell fakes or grey-market goods. Each order is carefully packed in Kobe, Japan and dispatched with full tracking.

FAQ

Is the strong cooling doing anything, or is it just a sensation?

It is a sensation. Menthol and borneol trigger the cold receptors on the eye surface; they are excipients, not active ingredients, and they are not part of what the Japanese approval credits with treating anything. The therapeutic work is done by the six actives listed above, which are present at the same kind of concentrations as in drops that feel like nothing. Pick the cooling level you find pleasant — you are not trading away effect.

Is this a medicine or a cosmetic?

A medicine. Japanese eye drops of this type are licensed under the Pharmaceuticals and Medical Devices Act and sold in pharmacies, not as cosmetics. That is why this page lists active ingredients with percentages and an approved indication list rather than beauty claims — and why you should check whether your country allows you to import an over-the-counter medicine before you order.

How strong is the cooling sensation?

Rohto Z! is the strongest-cooling drop in Rohto's consumer range, and the sensation is intense enough that some people find it too much. Japanese brands grade this separately from the actives, so a colder drop is not a stronger drop — the menthol only changes how it feels going in. If sharp cold is unpleasant for you, the milder versions in the same family contain the same kind of active ingredients.

Is this product halal or suitable for vegans?

Every active and every excipient in this formula is synthetic or mineral — there is no animal-derived ingredient and no alcohol as a solvent. The product carries no halal certification, because Japanese domestic medicines are almost never certified, but there is nothing in the published composition that would conflict with halal or vegan use.

How long does a bottle last once opened?

Japanese eye-drop inserts generally tell you to finish the bottle within about three months of opening and to discard whatever is left after that, because the preservative system is only validated for that period. Write the date you opened it on the carton. An unopened bottle keeps until the expiry date printed on the box, which is typically two to three years from manufacture.