As a result, Japan has some very strong over-the-counter medication to fight colds and flus. Many cold, flu, and pain-relieving drugs contain caffeine or other stimulants to fight fatigue and allow you to remain alert through your entire work day even if your head is foggy and you can't breathe out of your nose.

It's also very common to wear surgical masks if you're sick (much to the fascination of many a visiting foreigner), but it's mainly a courtesy to those around you, as even if you're hacking and dribbling, you're often still expected to come to work. A key exception is the flu: that stays home, whether you work in an office or in a school. With the population so tightly packed, every winter becomes a national battle to contain influenza!

With that in mind, here are some popular cold and flu medicines the you can expect to see in people's shopping baskets in Japan. These are mostly only available domestically, and be sure to check the ingredients if you ever plan to take any abroad—due to their constituents, some of these medicines are restricted overseas!

SS Bron, a cough syrup that's also designed for severe phlegm problems, is only supposed to be used when you’re suffering from a very severe cold or flu. Loosely related to oxycodone, it's restricted in many other parts of the world because of the dihydrocodeine it contains.

Eve A, which is a mixture of ibuprofen, a mild sedative and caffeine, is one of the best-selling painkillers in Japan. People use it to treat everything from a mild headache to a severe cold. Some Westerners complain that the dosage is too small and has to be adjusted based on your weight and level of pain, however. You're advised not to use heavy machinery or drive after taking Eve Type A because of the sedative constituent.

LuluAttack EX, made by Daiichi Sankyo Healthcare, is designed to treat sore throat, fever, runny nose, coughing and congestion. As this is one of the most popular cold and flu treatments, it's available at almost all drugstores in Japan, and very easy to come by!

This medicine is one of the most commonplace cold symptom treatments in Japan, used to combat fever, cough, runny nose, sneezing and pain, even for very strong colds. This medicine is also quite easy to find at most drugstores throughout Japan.