I HAVE A COCKER SPANIEL PUPPY 11 WEEKS OLD I WORMED HER WITH STRONG HOLD 2 WEEKS AGO SHE SEEMED OK FOR THE FIRST WEEK BUT NOW SHE IS BACK TO HAVING DIOHREA AGIAN,SHOULD I WORM HER AGAIN AS I AM A BIT CONCERNED AS THE STRONG HOLD IS SUPOSE TO WORK FOR 1 MONTH HELP

Have you changed her food in this time since you wormed her ?
Lel

If the breeder wormed her a couple of times before you got her, plus you using the Stronghold, then I doubt the prob is worms. If however this Stronghold dose was her very first worming then she may still have worms, I wonder if one dose would clear out all the adult worms+eggs and developing worms. I use Stronghold on my dogs and like it, but if she doesn't have mites (mange) it may be worth using a puppy wormer from the vet next time the Stronghold is due (2 weeks?) together with Frontline (for fleas/ticks) instead of Stronghold and then return to Stronghold when the Frontline "runs out". If she has been regularly wormed all along it is probably something else that is giving her the looseness. What are you feeding her on and as Lel asked - have you changed the diet?