Can dogs eat portabella mushrooms?

Can dogs eat portabella mushrooms? When I try to find the answer online I see responses saying, "NEVER let your dog eat mushrooms", but I get the impression that they are referring to the type found outdoors that could potentially be poisonous to anyone. I sometimes have vegetarian portabella 'burgers' that I would like to feed my dog on occasion but want to check on the safety of doing so first. I understand that 'people food' is not the best choice for dogs but my dog is twelve years old (Collie), in failing health, has lost twenty pounds (as evidenced at the last vet visit a few weeks ago) and I want to make her remaining months as pleasant as possible. I am basically giving her hospice care and she doesn't much care for kibble anymore and I find it difficult to even convince her to eat. She has difficulty (and often needs help) getting up and is presently taking 75 mg Rimadyl a day along with Glucosamine and one capsule of estrogen once a week for incontinence.

You know I searched for the answer to this forever, and never found a straight answers. Mushrooms growing outside can definitely be toxic to dogs, and I have read that some dogs can be allergic to "edible" mushrooms also. You could ask your vet, and see if they have any idea. My collie has eaten small bits of portabella in the past and never gotten sick, but I don't feel comfortable actually feeding her big pieces.

Maybe you could start buying non-mushroom veggie burgers? There's tons out there, you just have to watch out for onion in the ingredients.

My doggie has been vegetarian for 4 years, and I home-cook for her. :)

Im pretty sure all mushrooms are toxic to dogs.
i wouldnt feed him that.

maybe making homecooked meats or feeding some wet food would be enjoyable to your dogs.

also onions, garlic, chocolate, coffe, tea and grapes are amunst some fo the common foods that are toxic to dogs

I don't know about dogs, but one of my cats LOVES mushrooms (store-bought button type). She comes running out to the kitchen whenever I am cutting them up, somehow she knows. I have been feeding her mushrooms on an irregular basis since she was a kitten with no ill effect (she is 11 now). However, she doesn't eat more than a few small pieces at a time usually, maybe one mushroom at most. My dog doesn't seem interested, though my other cat occasionally will eat them too.

Chicken or lamb would likely be a better bet for her. When dawgs are in poor health and are becoming disinterested in their food it's better not to introduce foods that are new to you and them on the off-chance that it cause's them to have digestion issues.