Summarize the following:
Your veterinarian can provide you with drugs to ease the vomiting. Since you can only treat the symptoms of parvo, not the actual disease, this step is one of the most important to provide comfort for your dog. Your dog may also need a medication to control diarrhea.  Brace your dog against your body or a wall. Use one arm to hold him.  Fill the syringe with the amount recommended on the bottle. Insert it gently between the cheek and teeth.  Slowly push in the plunger. Let the medication drain into your dog's mouth. Though antibiotics will not do anything for the parvo, they will stop another infection from taking over. Your doctor can provide you with antibiotics, as well. Follow the directions on the bottle, and give the liquid orally as provided in the previous step. If your dog is particularly severe, your vet may need to provide pain relief, as well. You give this medication the same way as the others as needed. One study found that a using a certain medication regimen at home greatly increased a dog's chances of surviving. The first part of the regimen is giving a strong anti-nausea drug, Maropitant, once a day. The other part of the regimen is having the vet give one dose of long-lasting antibiotic under the skin when the dog is diagnosed (Convenia), and then having the pet parent give subcutaneous fluids 3 times every day. Ask your vet if these drugs are right for your dog.
Slow down the vomiting. Give antibiotics. Provide pain relief. Try the new parvo protocol recommended by Colorado State.