I haven't used the dog vaccine since I bought it. Can I use it now?

Whether the vaccine can be used depends on the situation.

It depends on whether the vaccine has passed its shelf life. If the warranty expires, throw it away.

See if the vaccine is properly stored, because the vaccine is generally stored at 2 ~ 8, which is the temperature of refrigerator insurance. If you find that the dry agent of the vaccine is no longer a block, but a powder, throw it away and think it has failed.