Will Falconer, DVM Moderator
Oh, sorry to hear this, Susan. Poor pup, now getting his immune system further weakened by antibiotics, after the Wham Bam Thank You Ma'am combo vaccinations started it all!
Still, phosphorus should help him get better much faster, and if she can hear reason and just stop the abi before he goes much further into sick gut land, you'll have served him. And nux vomica might even be the better fitting remedy, as he's now been intoxicated by the abi.
All the best.