Which OTC Loxoprofen Should You Choose? [By Purpose] ~ OTC Analgesic Three Kingdoms: Practical Edition

Note: This article contains affiliate links.

As announced in the previous article, I would like to start by comparing Loxoprofen-related products by purpose, including a cost-performance comparison.

For those who don't know what the 'OTC Three Kingdoms' is, click here...

0. Loxoprofen is still a [Category 1 OTC Drug]

On July 29, 2026, an article titled 'Loxonin to be available for purchase without a pharmacist; MHLW advisory panel approves with conditions' was published, but within that same article, it states:

So, it has not changed yet.

Therefore, at physical stores, you must purchase them from a pharmacist. (Even online, procedures such as confirmation of proper use by a pharmacist before shipping are required, so just clicking 'buy' does not guarantee it will be delivered automatically.)

Therefore, as of the time of writing this article, Loxoprofen products are still 'OTC drugs that require pharmacist confirmation.'
Please note that compared to acetaminophen or ibuprofen OTC drugs, it takes a little more effort to purchase. (However, personally, it is a medicine I want to have even if it takes that effort...)

Note that the single dose of Loxoprofen is 60mg as the anhydrous form, so the cost-performance comparison is also done per single dose. (Prices are based on Amazon prices at the time of writing.)

1. For those who are fine with any product containing Loxoprofen

To conclude,
If you have a brand preference: Yes => Loxonin S.
No
⇓
Need just one: Loxoprofen Tablets 'Kunihiro' 12 tablets
=> Need multiple: Purchase a set on Rakuten

① Loxonin S 12 tablets (approx. 47 yen per dose)

This product is almost identical to the medical-grade Loxonin. The medical drug price is 10.8 yen, so it is more than four times the price, but you cannot get medicine at the medical drug price at a pharmacy. Compared to drugs with other ingredients (especially allergy medicine, which I don't feel like buying when I see the drug price), it is a much more reasonable price.
=> If you want 12 tablets of just Loxonin and go to the hospital, it will cost at least 1,500 yen for a first visit and about 1,000 yen for a follow-up visit, so considering the waiting time, how cheap is this... A miracle drug✨

So, if you don't have a particular preference for the Daiichi Sankyo brand, you can just choose what is known as a 'generic' in medical terms.

② Loxoprofen Tablets 'Kunihiro' 12 tablets (approx. 35 yen per dose (approx. 20 yen if bought in a set))

This is the price when purchased individually on Amazon.

At 'Kusuri no Yanagawa' on Rakuten, you can purchase with free shipping starting from a 2-pack. You can specify the quantity a bit more precisely, but:

■ 2-pack (approx. 31 yen per dose)

■ 12 tablets, 12-pack (approx. 20 yen per dose)

There is talk that Yodobashi Camera is the cheapest for single-unit purchases, but since I cannot place affiliate links, I will only provide the information... If you are a Rakuten user and want to buy 2 or more, I think '
Kusuri no Yanagawa' is a good choice. (This is my impression based on point returns, etc., at the time of writing this article.)

3. Other Loxoprofen single-ingredient products

On Amazon, as far as I can see, the only Loxoprofen other than Daiichi Sankyo is 'Kunihiro', but if you search online, various brands will appear. There might be many others, but since it costs about 20 yen per dose for a 12x10 pack, please use that as a guide when choosing.

(1) Vitatrell Loxoprofen Tablets 12 tablets
'Kusuri no Yanagawa' lineup
■ From 10 packs or more, this one is cheaper (approx. 20 yen per dose)

(2) Loxoprofen Tablets NX
feels like it doesn't differ much in price from 'Kunihiro'. (It's a little more expensive, but since some have good point return rates, it might be cheaper if you take that into account.)

(3) Loxoprofen Tablets 'CH'
also feels like it doesn't differ much in price from 'Kunihiro'. The price on the label is cheap, but you might lose out if others have higher point return rates.

2. Only ingredients that are gentle on the stomach are added

<very small> Honestly speaking, isn't Loxonin S enough? </very small>

Loxonin S Plus 12 tablets (approx. 53 yen per dose)

Magnesium oxide is 'added' to Loxonin S.

Loxoprofen is a prodrug that changes into an active form after being absorbed into the body, and it is an ingredient designed to reduce the direct burden on the stomach. Since magnesium oxide, which has efficacy as a stomach medicine (antacid), is added to it, the package says that ingredients gentle on the stomach are added.

However, I remember learning in college that magnesium oxide is an antacid, but in actual practice, I have only ever seen it used as a laxative. (Well, I think it's because many excellent stomach medicines have been released since then.)

3. I want it to take effect as quickly as possible

It's not that much more expensive than Loxonin S, so it might be worth trying once?

Loxonin S Quick 12 tablets (approx. 64 yen per dose)

The phrase "works fast" is interesting because there are various issues surrounding it in pharmaceutical advertising, but the reason it is okay to clearly state it on the package is:

Tablet disintegrates quickly => The process until the active ingredient dissolves is short
=> (Compared to those that dissolve slowly) faster onset of effect

This is the syllogism. What is asserted on the product page is only up to "disintegrates quickly." (I think they are pushing the limits quite a bit.)

Also, since I haven't seen the actual tablets, I can't say for sure, but I think the reason they come in a full aluminum sheet is that the formulation has high hygroscopicity to speed up disintegration. If you put them in your bag without a cover or case, there is a risk that the sheet will get punctured and the tablets will become unusable (or difficult to use), so it might not be a formulation suitable for a careless person like me. (I once had an experience where another medicine got punctured and became unusable.)

Furthermore,
it also contains 100 mg of an ingredient called magnesium aluminometasilicate per dose. This same ingredient is also included in a stomach medicine called KM Powder, but that KM Powder contains 400 mg per dose, and it also contains other stomach medicines. So, well, regarding this...
<very small>(I suspect they just added it as an additive and decided to list the stomach benefits as a bonus...)</very small>

Taisho Pharmaceutical used to sell products called Naron Loxy and Loxoprofen T Liquid, which were designed with rapid efficacy in mind in terms of formulation, but they seem to have been discontinued, perhaps because they couldn't differentiate themselves, and are no longer available.
(Honestly, I learned for the first time that such medicines existed by writing this article.)

4. Headache (designed for efficacy against)

For those who think Loxoprofen works but want a little more effect... please try this once.
*Please note that there is a warning not to drive after taking it (as there is a high possibility of drowsiness) because it contains allylisopropylacetylurea.

Loxonin S Premium 24 tablets (approx. 84 yen per dose) *May cause drowsiness

This is a product that even says on the package, "Designed for efficacy against headaches."
Both the contents and the price are premium.

The most important thing to be careful about with this product is that it is a medicine where you take 2 tablets per dose.
"Oh, it has 24 tablets, so it's for 24 doses" is a misunderstanding, so please be careful.

Ingredients in the product other than Loxoprofen
Allylisopropylacetylurea: 60 mg
Anhydrous caffeine: 50 mg
These are formulations that have been used for a long time in Japanese combination antipyretic analgesics. (SG Granules, a medical headache medicine used since ancient times, contain 150 mg of isopropylantipyrine and 250 mg of acetaminophen instead of loxoprofen, so they are very similar.)

Allylisopropylacetylurea is not widely used globally, but since 250 mg of acetaminophen + 250 mg of aspirin + 65 mg of caffeine is sold as an OTC migraine medicine in the United States, it can certainly be called a "formulation designed for headaches." (However, caffeine is also contained in coffee and energy drinks, and excessive intake can conversely cause headaches. Please be very careful about caffeine intake while taking this medicine.)

(Regarding the inclusion of magnesium aluminometasilicate, I also wrote about this for Loxonin S Quick <very small>I suspect they just added it as an additive and decided to list the stomach benefits as a bonus...</very small>

5. Menstrual pain (designed with the mechanism of)

Loxonin S Premium Fine 24 tablets (approx. 87 yen per dose)

This is a product "designed with the mechanism of menstrual pain in mind." This is also a medicine where you take 2 tablets per dose, so be careful when calculating costs.

As for the ingredients,
Peony root dry extract: Peony root (shakuyaku) is commonly found in Kampo medicines used for menstrual pain, such as Shakuyakukanzoto, Tokishakuyakusan, and Keishibukuryogan. Hesperidin is the main component of Chenpi (dried citrus peel). And, as for a Kampo medicine that uses peony root and Chenpi and is also effective for menstrual pain, there is one called Goshakusan.

I don't know if the manufacturer was conscious of Goshakusan, but the formulation design itself, which combines peony root + hesperidin with menstrual pain in mind, is quite interesting. I think you can expect a "fine" effect that is "premium" for menstrual pain.

Since I cannot share my own personal experience regarding this, I
checked review sites for reference, and it seems to be generally well-received.

(Regarding the inclusion of magnesium aluminometasilicate, as I wrote for Loxonin S Quick, since it was used as an additive, I suspect they might have just added the stomach-related benefits as a bonus...)

Note that while Loxoprofen Tablets "Kunihiro" come in pink packaging designed with menstrual pain in mind, the ingredients and their amounts are the same as the standard blue packaging. Please be aware that the price may sometimes be slightly higher...

6. Pain caused by stiffness in the shoulders or lower back

It is a medicine that is like Loxonin plus Shakuyakukanzoto. Since both are indispensable to me, I decided that I would buy this if I ever ran out of my current medicine.

Loxonin PRO Physical 24 tablets (approx. 94 yen per dose)

This is a product aimed at "lower back and shoulder pain." Since this is also a medicine where you take 2 tablets per dose, please be careful when calculating the cost.

Although the product says it is for lower back and shoulder pain, loxoprofen is sufficiently effective against inflammatory pain. As for what the difference in ingredients is, it contains
dried peony extract
and
dried licorice extract. Although the amount contained is nowhere near the amount used in Shakuyakukanzoto,

While it is not accurate in terms of the blending ratio or amount,
it is a medicine that is like Loxonin plus Shakuyakukanzoto. Since both are indispensable to me, I decided that I would buy this if I ever ran out of my current medicine.

(Regarding the expectations for the medicinal effects of magnesium oxide, I wrote about it in the Loxonin Plus section, but... well, I'm not so sure about that.)

Summary

In the end, which Loxonin® should you choose?

The standard one is fine → Loxonin S
(Medicines other than Daiichi Sankyo's are basically almost equivalent to this)

Want to add a little consideration for the stomach → Loxonin S Plus

Want it to work as quickly as possible → Loxonin S Quick

Want to prioritize effectiveness for headaches → Loxonin S Premium
*Contains ingredients that cause drowsiness; be careful when driving

Want to choose with menstrual pain in mind → Loxonin S Premium Fine

Pain caused by stiffness in the shoulders or lower back → Loxonin PRO Physical

Next time, I will examine medicines containing ibuprofen, which have existed for a long time in terms of ingredients, and therefore, conversely, have many different types of medicines available.

Thank you for reading until the end.

[Serious Playfulness from a PhD in Pharmacy] Series