Worried about the new food you're eating? Chew some charcoal, which can help your body deal with weird bacteria in foods that you're not used to and keep you from getting sick.
This is another way to get a punch of Vitamin C. Lots of people add it to their bottled water to drink while traveling and being subjected to a lot more germs than normal.
Use this before and after air travel to give your immune system a boost.
Whether you have allergies or not, keep some antihistamines with you in case you come across something that gives you an allergic reaction. These can also help with itchy situations and hives.
You can pick up chewable allergy tabs as well.
Maybe you've woken up with a headache or cramps or have minorly hurt yourself and need a bit of help with the pain. Ibuprofen can be used for a lot of things and aren't as harsh as traditional aspirin and other pain relievers.