I do not know that weight really enters in to it.
My 100 pound German Shepherd is a breeze to pill. Although she hates it she will just sit and let me pretty much stick the pill down her throat (she, like the OP’s dog, easily gets around any tricks to get her to eat them). If she was of a mind to she could easily remove a few fingers of mine at that point but she never does.
My 12 pound cat however is impossible to pill. Just flipping impossible. That cat thwarted two adults working in tandem to give her a pill. My (now ex) wife and I presumably have bigger brains and more than 20x the weight on our side and the cat humbled us with no trouble. We even tried wrapping it up in a towel to fully immobilize it…still did not work. In the end we just had to hope the cat would survive without her pills (she did).
I use those daily on one of our cats, even though she USED to eat the pocket and spit out the pill. My sneaky plan to retrain her worked, though: I got a package of the *other *flavor of Pill Pockets and gave her an empty one for three days in a row, at the same time every day, making sure her brother was nearby so she’d chuck it down in a hurry to keep him from stealing it; since then I give the full-of-pill pocket at that same time, and it’s become routine.
We’ve used the a pill shooter like Q.E.D. linked to, with some success, though with some critters the hardest part is catching/securing them in the first place if they know what’s coming. It sounds like that’s a big part of your trouble.
Do you have access to an assistant?
Elly is getting wilier by the day. I had some minor success with sneaking the pills into egg salad and then acting like I was going to take it away from her–she scarfed it down as quickly as she could until the 2nd or 3rd time I tried it. Then she got suspicious and we went back to square one.
She’s almost done with the meds now. Thank goodness, because she was totally onto me when I mixed it with ground turkey. It was NOT a pretty sight, but I finally got them down her. That dog has the longest snout I’ve ever had the misfortune to shove a pill into.
I’ve had worse pet-pilling adventures, especially with cats and one long-ago Chow, but this is difficult because she looks so miserable–all stopped up and unhappy, and looking at me with those big guilt-inducing eyes.
Here are my favorite instructions for pilling a cat: http://www.xs4all.nl/~josvg/pets/cat-pill.html
Could’ve written that myself.