Agreed. The dog thing just got tacked onto my post about snakes. But, hey, they're animals. I'll allow it.
Back to the snake thread. Make sure you always have Benadryl on hand at your house. If your dog is bitten you can give them Benadryl at 1mg per pound of body weight, although it is REALLY hard to OD on Benadryl, so you don't have to be exact. We give the big dogs two full 25 mg caplets when they are bitten and leave it at that, even though they weigh a little more than that.
You can dose them every 6 hours or so and it helps keep them calm and prevent an allergic reaction to the bite. It won't do anything for the pain, which is extreme, but it will calm them and maybe get them to sleep a little.
Copperhead bites are rarely fatal for dogs or humans, but they do allegedly hurt exquisitely. Most danger comes if they are bitten somewhere that the swelling will cut off their air supply, or if they are bitten on the torso, closer to their organs.
Copperheads are pit vipers, so their venom is necrotizing, causing tissue damage. that is why you don't want a bite close to an organ. Bites on the face, lips, paws, legs, etc. are much better, although they will swell a lot, look really gross and there will be a lot of pain.
Also, because the venom causes tissue damage, it is not uncommon for the wound to "weep" and then have the flesh around it slough off as it is healing. It will leave an open wound you need to keep clean while it heals.
Obviously going to the vet is the safest thing to do, but they usually won't be able to do much except put them on an IV to minimize the tissue damage. They usually won't use the anti-venon unless the dog is in dire straits. They won't use it at all if you can't prove it was actually a copperhead. (as in you will need the dead snake for proof or they are unlikely to use the anti-venon.)
Anyway, I have plenty of snake bite aftermath stories if you have any questions!