CoQ10 Update

CoQ10 is necessary for energy production in every cell in your body, and is particularly critical in the heart muscle. It is also one of the key enzymes that regenerate the antioxidant vitamins in your body, such as Vit-C & E that become oxidized as they neutralize free radicals.
However, recent research (reference?) shows that most of your store bought CoQ-10 comes in the oxidized form and is useless in this role of re-energizing. How can you tell? Just poke a little hole in the capsule and squeeze a little out onto something white. If it is bright orange, it is the oxidized (or useless) form. Did you get it at a 'bargan price'? For sure you will find it oxidized.
Another fact is that your body produces CoQ-10, but this production starts decreasing after age 25 or so. By your 50's it is dramatically less.

Here is a list of common medications that lower levels of C0Q10 in the body:

Statins for cholesterol , including atorvastatin (Lipitor), lovastatin (Mevacor), pravastatin (Pravachol, and simvastatin (Zocor).

Fibric acid derivatives for cholesterol, including gemfibrozil (Lopid).

Beta-blockers for high blood pressure, such as atenolol (Tenormin), labetolol (Normodyne), metoprolol (Lopressor or Toprol), and propranolol (Inderal).
Tricyclic antidepressant medications, including amitriptyline (Elavil), doxepin (Sinequan), and imipramine (Tofranil).

Also see Univ of Maryland and Wikipedia