My friend caved and got vaccinated. First with AstraZ, then a second shot of pfizer, about 4 weeks ago. She didn't have any immediate side effects for either. She is not feeling great today so fingers crossed she will be okay. The pharmacy gave her receipts as is the norm here in Ontario. Here is a part of the AstraZ receipt. Not sure if the expiry date is a use by date or effectiveness expiry date. Anyone have details on this topic?