No, silica gel packs are not poisonous to dogs. Silica gel is a desiccant, which means that it absorbs moisture from the air. It is often used to keep food and other items dry. Silica gel packs are typically made of small, porous beads that are composed of silicon dioxide, which is a natural mineral.
Although silica gel is not poisonous, it can still be harmful to dogs if they eat it. The beads can cause intestinal blockage, which can lead to vomiting, diarrhea, and abdominal pain. If your dog eats a silica gel pack, it is important to contact your veterinarian immediately.