TOKYO, June 2, 2025 - (JCN Newswire) - Eisai Co., Ltd. announced today the launch of “Pariet®S” (pharmaceutical requiring guidance), which is highly effective in alleviating severe heartburn andstomach pain caused by gastric acid reflux, at pharmacies and drugstores throughout Japan.(1)

"Pariet S" is the first proton pump inhibitor (PPI(2)) to receive manufacturing and marketing approval as an over the counter (OTC) medicine in Japan. Rabeprazole sodium, in an amount equivalent to that used in the prescription product(3), works directly on the proton pumps that produce stomach acid, effectively alleviating severe heartburn caused by gastric acid reflux and stomach pain due to excessiveacid secretion. The medicine comes in small, easy-to-swallow tablets, with a once-daily dosage providing 24-hour relief.

Rabeprazole sodium, the active ingredient in “Pariet S”, is a PPI developed at Eisai’s Tsukuba Research Laboratories. The medicine was first launched in Japan in 1997 as a prescription pharmaceutical underthe brand name “Pariet” and has since been approved more than 100 countries worldwide. It is widely prescribed to people struggling with acid-related disorders.

In recent years, there is a tendency for increased stomach acid secretion due to disrupted eating habits, stress, and a decline in the infection rate of Helicobacter pylori. Moreover, the number of individuals experiencing gastric acid reflux has grown, driven by age-related weakening of the lower esophageal sphincter. Eisai will introduce “Pariet S” as a new treatment option in the OTC gastric medication market, aiming to alleviate sever heartburn and discomfort caused by gastric acid related conditions, and strongly support people in the daily living domain who wish for a comfortable and secure daily life.

For further details, please refer to the product’s website for details about "Pariet S" (Japanese only) https://www.eisai.jp/products/pariet/pariets

(1) "Pariet S" is classified as a drug that requires a pharmacist’s guidance at the time of sale
(2) Proton Pump Inhibitor suppresses gastric acid secretion by inhibiting the “proton pump” which is the final step in the secretion process.
(3) Contains rabeprazole10mg per tablet

Media Inquiries:
Public Relations Department
Eisai Co., Ltd.
+81-(0)3-3817-5120

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