Recent visitors to Cat Street near Harajuku might have noticed a curious little pop-up giving away bottles of pills.

A neon red cross glowed behind the counter while two women in white lab coats showed customers scientific-looking charts on clipboards.

Hangover cure after a night out? Not exactly.

The sign outside read Fast Food Aid. Panels inside explained the concept: The customer hands over a fast-food restaurant receipt and, in return, receives a bottle of food supplements customized to replace the nutrients missing from that meal … for free.

Public service? Nah.

Fast Food Aid turns out to be part of a clever marketing campaign for a chain of restaurants specializing in the okonomiyaki savory pancake.

Dohtonbori is promoting a new restaurant opening in Hiroo (on May 26) by cheekily spelling it out: The healthy ingredients in Dohtonbori’s healthy okonomiyaki have all the nutrients you need.

The campaign is part of Dohtonbori’s recent makeover, which includes a new emoji-like logo and “Tasty-healthy” slogan. It is also announced the chain’s new policy of only using domestically grown vegetables by issuing a public apology for “not having done so earlier.”

The Fast Food Aid popup ends on May 4, but you can always go to any of the Dohtonbori stores later for a fix.