Emergen-C is a powdered supplement containing Vitamin C and others, such as B, along with complementary minerals. Some varieties contain other stuff like lycopene or amino acids. It comes in a tiny pouch. You open it, pour the contents into a glass of water, and then drink it down. It's a fizzy drink, similar to Alka-Seltzer but with more nutrients.
In 1978 the Alacer Corporation began manufacturing Emergen-C in Foothill Ranch, California. The company spent six years researching megadoses of Vitamin C with the consultation of Nobel laureate and vitamin C advocate Linus Pauling. The key ingredient of their formula is the 1000 mg of Vitamin C.
The powder is a novel form of delivery in that many vitamins, B in particular, require sufficient hydration in order to be fully absorbed. A person can adjust how much water they add to their packet. The more water added, the less fizzy the drink becomes. The level of fizziness decreases with time also, which is useful for those with sensitive stomachs.
There are currently over 10 flavors of Emergen-C, three flavors of Emergen-C Kidz®, and specialty formulas which address specific areas of the body such as joints, the immune system, bones, and the heart.
All of the flavors which I have tried taste great. Better than a chewable vitamin and mixing up the powder is a lot easier than trying to swallow a bunch of pills. Emergen-C is a good thing to take when you are soon to undergo a high level of bodily stress, such as a race. Emergen-C can help you do amazing things. Plus the packets are a lot easier to carry around then vitamins in pill form, if you aren't taking it every day.
Emergen-C is carried by reputable health food stores and some drugstores. They can be purchased individually for under a dollar or in a box of 30 for around 15 USD.
Alacer has donated many packets of their product to US forces in Iraq and Afghanistan.
Nearly 500 million packets of Emergen-C are sold annually. Alacer is currently the leading brand-name provider of vitamin C in the US. Similar products from other companies (such as Airborne) have attempted to emulate Emergen-C but have not done as well commercially. The reason for that is likely due to marketing, as the makers of Airborne specifically targeted the frequent flyers as being in need of extra protection against airborne illnesses. The grand, sweeping claims made by that company got them in hot water and they were roundly criticized as selling snake oil. Alacer wisely shied away from making any specific claims as to the benefits of Emergen-C. So don't think of Emergen-C as a cure for the common cold but rather a healthy alternative to Gatorade.
If you contact Alacer via their website, they will gladly send you free samples.