Having some antibiotics in your medical kit is a good thing but remember that taking any kind of antibiotic or other immune boosters when not needed can have very bad results. Your body needs germs to build a better stronger defense. There is only 76 reported colds and or symptoms. Thus the reason children catch colds easy and older people not so much as they have already had that cold and their immune system built up a defense against that particular germ or germs. If you MUST take some kind of immune booster do as Ken stated and eat good food and I recommend going herbal also as this will give your body a slight boost but not in a harmful way.
Cayenne pepper contains the chemical capsicum, a rich source of vitamin C that aids your immune system in fighting colds and flus. The powerful effect of vitamin C comes from bioflavinoids that help your body produce white blood cells, especially the white blood cells of your lymphatic system that cleanse your cells and tissues of toxins. Cayenne pepper, also full of beta carotene and antioxidants that support your immune system, helps build healthy mucus membrane tissue that defends against viruses and bacteria. Spicy cayenne peppers raise your body’s temperature to make you sweat, increasing the activity of your immune system.
A blue-green algae that often pops up in questionable-looking Day-Glo-colored “health food” drinks, spirulina can’t be counted out on appearance alone. There is serious evidence that it has a variety of potentially helpful uses, including strengthening immunity, says Patel. Animal research on spirulina is strong; and though there hasn’t been much testing done on humans, one 2008 study did find that taking 2g of spirulina a day for several months helped some men and women to overcome nasal allergies. “Spirulina is very safe, and may help to lower inflammation in the body, improving overall health as well,” Patel adds.