mini schnauzer vomiting blood and wretching

My 2 year old mini-schnauzer has been vomiting small amounts blood the last few days and is now wretching like she has something lodged in her throat.  I have taken her to the same vet 3 times in 5 days and the vet put her on prednisone, an anti coughing drug, an antibiotic, and vitamin k.  The blood work came back with elevated red blood cells.  My dog is still going to the bathroom.  My dog won't eat or drink and wretches then her whole body shakes after these episodes.  Can anyone help me out?  Another vet, an xray of her throat, etc???

[Aleda M Cheng, D.V.M., C.V.A]

Please take your dog to an emergency vet.  She could have been exposed to a toxin, a foreign body, or just has kennel cough.  If she has had no improvement under the current therapy regimen than further diagnostics must be performed, including chest X-Rays, blood cultures and more.