The right common carotid artery arises from the brachiocephalic trunk (posterior to the right sternoclavicular joint), whereas the left common carotid is a branch of the arch of the aorta and hence has a thoracic portion before it reaches the neck (posterior to the left sternoclavicular joint).
Metformin Dosing. The recommended starting dosage of metformin is  500 mg twice daily. The maximum dosage for children age 10 to 16 is 2000 mg, and for adults age 17 and older is 2550 mg. Your dose should be increased only when necessary and should be increased slowly in order to avoid side effects.
1 Metformin with a sulfonylurea: Your doctor will determine the dose of each medicine. 2  Metformin with insulin: At first, 500 mg once a day. 3  Then, your doctor may increase your dose by 500 mg every week if needed until your blood sugar is controlled. 4  However, the dose is usually not more than 2500 mg per day. Metformin with a sulfonylurea: Your doctor will determine the dose of each medicine. 2  Metformin with insulin: At first, 5 mL once a day. 3  Your doctor may increase your dose if needed until your blood sugar is controlled. 4  However, the dose is usually not more than 25 mL per day.