Do you need to be a member to purchase medicine?

That's a good question. I am not 100% sure, but you can ask them while you are there. I don't want to tell Yes or No and I be wrong. I honestly have never brought medicine from Costco.

I'm not 100% sure.

I would assume yes, because you cannot even enter the store without showing your card!

Yes only if you have a membership card you can buy n the store