Hello, I'm Dr. Deb.
I recently came online and see that your question about Molly hasn't been answered. I'm so sorry that you've had to wait for a response,but if you still need assistance, I'd like to help if I can.
First, let me tell you how sorry I am that Molly has been diagosed with cancer. I know how distressing this must be for your entire family.
To answer your question, domperidone can be given to dogs as an anti-vomiting agent although it's not used in small animals very often. It is primarily metabolized and excreted through urine and feces.
As to Cautions with it's use, the following is taken from Plumbs Veterinary Drug Handbook:
Domperidone should not be used in animals with known hypersensitivity to it or when GI obstructions are present or suspected.
Because domperidone is potentially a neurotoxic substrate of P-glycoprotein, it should be used with caution in those herding breeds (e.g., Collies) that may have the gene mutation (MDR1) that causes a nonfunctional protein.
1. Opioids may reduce the efficacy of domperidone
2. It may alter the absorptive characteristics of sustained -release or eneteric coated oral medicaions by decreasing GI transit times
The dose would be 2–5 mg (total dose) two to three times a day. While it would be illegal for me to advise you to use a drug which has been dispensed for a human, I can provide the dosage information for a canine patient which I have done.
I hope this helps although, again, my apologies for the delayed response. Deb