Icky metro train advert featuring "Mr. Contac."
I would think that this kind of remedy -- a pill that turns off your runny nose -- would be particularly useful here in Japan, not just because sakura season brings wicked hay fever to many people, but also because it's considered impolite to blow your nose in public, though apparently you are permitted to quietly dab at the drips with a tissue, and to sniffle, all day long if necessary. And if you are seated next to me on a plane, go ahead and sniff like a coke addict for the entire 13-hour flight, just do not, God forbid, honk into a hankie.
This reminds me of a little fun fact about the free Kleenex that's regularly handed out near train stations and outside shops. My understanding (and someone correct me if I'm wrong) is that this practice of distributing coupons and ads tucked inside packs of tissue became popular because public restrooms didn't have toilet paper, hence, few would refuse -- gotta have something in your purse just in case, right? But nowadays, many public facilities if not most do make the loo roll available, and yet the free tissues are still out there for the taking. If you're in the market for some, try the busy corners near Shibuya station and outside Docomo and Softbank stores.