What is coenzyme Q10?

I've been struggling with bronchitis for a while now and thought I'd add CoQ10 to my vitamin and supplement regime. But first, I wanted to find out more about it.

The from WebMD:

Coenzyme Q10 (CoQ10) is a substance similar to a vitamin. It is found in every cell of the body. Your body makes CoQ10, and your cells use it to produce energy your body needs for cell growth and maintenance. It also functions as an antioxidant, which protects the body from damage caused by harmful molecules. CoQ10 is naturally present in small amounts in a wide variety of foods, but levels are particularly high in organ meats such as heart, liver, and kidney, as well as beef, soy oil, sardines, mackerel, and peanuts.

What is it used for?

Many claims are made about CoQ10. It is said to help in cardiovascular conditions, especially heart failure, as well as cancer, muscular dystrophy, and periodontal disease. It is also said to boost energy and speed recovery from exercise. Some people take it along with some other medicine to reduce the side effects of that medicines on the heart, muscles, and other organs.

Is it safe?

Taking 100 mg per day or more of CoQ10 has caused mild insomnia in some people. And research has detected elevated levels of liver enzymes in people taking doses of 300 mg per day for long periods of time. Liver toxicity has not been reported.

Here's the link for the full skinny on CoQ10 from WebMd.