Eisai Launches Japan's First Over-the-Counter Proton Pump Inhibitor Pariet S

Key Insights

• Eisai Co. has launched Pariet S, marking the first proton pump inhibitor to receive over-the-counter approval in Japan for treating severe heartburn and stomach pain.
• The medication contains rabeprazole sodium at the same 10mg dosage as the prescription version, providing 24-hour relief with once-daily dosing.
• This launch addresses growing gastric acid reflux cases driven by disrupted eating habits, stress, and age-related weakening of the lower esophageal sphincter.

Eisai Co. has announced the launch of Pariet S, Japan's first proton pump inhibitor (PPI) approved for over-the-counter sale, marking a significant milestone in gastric acid disorder treatment accessibility. The medication is now available at pharmacies and drugstores throughout Japan as a "pharmaceutical requiring guidance."

Breakthrough OTC Approval

Pariet S contains rabeprazole sodium at 10mg per tablet, equivalent to the prescription formulation, making it the first PPI to transition from prescription-only to OTC status in Japan. The medication works directly on proton pumps that produce stomach acid, effectively alleviating severe heartburn caused by gastric acid reflux and stomach pain due to excessive acid secretion.

The small, easy-to-swallow tablets require only once-daily dosing and provide 24-hour relief from symptoms. As a pharmaceutical requiring guidance, Pariet S must be dispensed with pharmacist consultation at the time of sale.

Established Clinical Foundation

Rabeprazole sodium, the active ingredient in Pariet S, was developed at Eisai's Tsukuba Research Laboratories and first launched in Japan in 1997 as the prescription medication Pariet. The drug has since gained approval in more than 100 countries worldwide and is widely prescribed for acid-related disorders.

Addressing Growing Medical Need

Recent trends show increased stomach acid secretion due to disrupted eating habits, stress, and declining Helicobacter pylori infection rates. Additionally, the number of individuals experiencing gastric acid reflux has grown, driven by age-related weakening of the lower esophageal sphincter.

Eisai positions Pariet S as addressing these evolving healthcare needs by providing a new treatment option in the OTC gastric medication market. The company aims to support individuals seeking relief from severe heartburn and discomfort caused by gastric acid-related conditions in their daily lives.

Market Impact

The launch represents a significant expansion of treatment options for consumers managing acid-related gastric conditions without requiring prescription access. By making PPI therapy available over-the-counter for the first time in Japan, Eisai is responding to the growing prevalence of gastric acid reflux and related symptoms in the Japanese population.