you can take both the vit.
for doses you should always mention the reason for the treatment as doses differs in all cases
still i will tell you
The RDA is 60 mg, per day - yet this amount will only prevent you from picking up scurvy
and more recent studies suggest that an intake between 200 - 500 mg per day may be the most beneficial for healthy people.
The recommend dosage for pregnant or lactating women is 75-95 mg per day.
and if you are smoker u need to add 100 mg extra.
consult your doctor and than only start any medication to have healthy effect dont self medicate.