For real Japan? Your conbinis are half the reason I have a hangover, and your conbinis have EVERYTHING! How could I have missed this before? I suppose I was blinded by the vast selection of bread, desserts, beer, snacks, facial wash, magazines, onigiri, gum, hair wax, makeup, t-shirts, cell phone chargers, chu-hai, cup noodles, and thousands of genki drinks.
Even my phone was hungover when I took this picture
I had to walk about 20 minutes towards the station, passing 2 Lawsons and 3 Family Marts, just to get to a drug store. I really should have brought my bike to Tokyo.
If you need medicine, look for the 薬 sign. Drug stores (yakkyoku 薬局) will have everything you need to treat your hangover, and any other ailment you may be experiencing. Heads up though, Japanese medicine will help you fight your colds, but many of my American friends who grew up taking antibiotics with their morning cereal are not satisfied with the strength of Japanese medicine.
Yakkyoku also tend to have cheaper prices on snacks than conbinis. Its not uncommon to find Jyagariko and Onigiri Senbei for around 60-80 yen where prices are as high as 160yen in conbinis. The down side is that yakkyoku are few and far between compared to the Family Marts on every corner, so stock up on that ibuprofen and Pocari Sweat beforehand.