@grrranny, good question!

My doctors recommend I take 100 mg ubiquinol type of CoQ10 twice a day, same as @seniormed. It depends on age, health and condition it is being treated. Your doctor will be able to tell you what is best for you.

From Mayo Clinic
- CoQ10 Overview: https://www.mayoclinic.org/drugs-supplements-coenzyme-q10/art-20362602

- Testing and treating with diet: If you are worried that your coenzyme Q10 level is low, you can have it checked with a blood test at your doctor’s office. If it is lower than normal, then you may first want to consider making changes to your diet. For most people, eating at least five fruits and vegetables a day, fish two to three times a week, and nuts two to three times a week keeps their coenzyme Q10 level normal, even if they are taking a statin.

- Supplementation: If your coenzyme Q10 level stays low after you have incorporated these foods into your diet, then taking a supplement may be appropriate. Coenzyme Q10 supplements are available over-the-counter at most pharmacies. You may see them under the names “ubiquinone” or “ ubiquinol.” Ubiquinol tends to be better absorbed than ubiquinone, and the ideal dose is typically 200 mg once per day. Most of the time, ubiquinol is sold in a gel-based or liquid-based capsule.

What condition are you taking CoQ10 for? Do you plan to visit with your doctor for recommendations?