TOKYO—It’s the hottest season of the year in Japan, and that means it’s eel season. So, bottom’s up!

A canned drink called “Unagi Nobori,” or “Surging Eel,” made by Japan Tobacco Inc., hit the nation’s stores this month just ahead of Japan’s annual eel-eating season, company spokesman Kazunori Hayashi said Monday.

“It’s mainly for men who are exhausted by the summer’s heat,” Hayashi said of the beverage, believed to be the first mass-produced eel drink in Japan.

Many Japanese believe eating eel boosts stamina in hot weather.

The fizzy, yellow-colored drink contains extracts from the head and bones of eel and five vitamins—A, B1, B2, D and E—contained in the fish.

The Japanese particularly like to eat eel on traditional eel days, which fall on July 24 and Aug. 5 this year.

Demand for eel is so high that Japan has been hit by scores of eel fraud cases, including a recent high-profile incident in which a government ministry publicly scolded two companies for mislabeling eel imported from China as being domestically grown.

The eel involved in recent scandals was prepared in a popular “kaba-yaki” style, in which it is broiled and covered with a sweet sauce. The $1.30 drink costs about one-tenth as much as broiled eel, but has a similar flavor.

Eel extract is also used in cookies and pies made in Japan’s biggest eel-producing town, Hamamatsu.