“I think my dog ate a pack of gum,” the caller said when I answered the phone at 9 pm. I had already worked a 12-hour day, but I was still the veterinarian on call for the Vineyard overnight. Please, oh please, let it not be sugar-free gum, I thought. “Sugar-free?” I asked casually. “Yes,” he replied. Please, oh please, let it be a big dog and just a little gum. No such luck. Jack, the dog in question, weighed 34 pounds, and might have eaten 10 pieces of Trident Tropical Twist Sugarfree gum containing xylitol within the last hour.
Xylitol was first used as a substitute sweetener during World War II when sugar supplies were limited. It later gained popularity when it was found to have some beneficial effects, such as antibacterial properties which lessen tooth decay and periodontal disease. It even has been touted to help with conditions like osteoporosis, uterine fibroids, and breast cancer. It can be found in products such as toothpaste, mouthwash, gum, mints, cakes, candy, and peanut butter.
So why was I even concerned about Jack? Because the canine pancreas reacts differently to xylitol than the human pancreas. In people, xylitol is absorbed very slowly into the body without provoking any significant insulin release. Jack’s doggy pancreas responds differently. It gets confused and thinks that xylitol is a super-duper sugar bomb. His pancreas does what a pancreas is supposed to do with a super-duper sugar bomb. It releases a blast of insulin. A hugely exaggerated blast. Sometimes as much as three to seven times the amount of insulin it would make in response to the same portion of real sugar. But there is no real sugar so Jack’s blood glucose levels plummet, sometimes causing profound, potentially life-threatening hypoglycemia.
The first sign of xylitol toxicosis is usually vomiting, followed by lethargy, weakness, disorientation, collapse, seizures, and, sometimes, death. Onset of symptoms is usually rapid — as little as half an hour after ingestion — but may be delayed as long as 12 hours. Hypoglycemia may persist for a day or more. Ingestion of very high doses can also cause liver damage, often progressing to acute liver failure and death within three days.
I needed to know quickly how much xylitol was in that gum. Different brands contain different amounts.There are even extreme variations depending on flavor. For example, one type of gum has 9 mg of xylitol per piece while another flavor has 700 mg. And they don’t list these numbers on the package! If Jack ate one of the more concentrated varieties, he might need to be hospitalized and observed throughout the night with an intravenous catheter and continuous dextrose drip. He might need frequent monitoring of blood sugar levels as well as electrolytes, liver enzymes, and clotting times. All this would require him to be transferred tonight to a 24-hour ICU facility off-Island. “The last ferry is leaving right now,” I told Jack’s dad. “If we have to transfer him tonight, we can get you on the Patriot boat. It depends how high a dose he ingested.” I suggested he call the animal poison hotline. Their veterinary toxicologists have immediate access to the information needed, i.e. the xylitol content for Trident Tropical Twist, and they would recommend a treatment protocol, including helping us decide if he needed to head off tonight.
“Call back as soon as you have spoken with them,” I said. “Then come over ASAP so we can induce vomiting.” Ideally we should induce vomiting within 30 minutes of ingestion as xylitol is absorbed extremely rapidly. It was probably already too late, but still worth a try. I waited anxiously by the phone. What if Jack’s blood sugar dropped so low he seizured? I couldn’t put them on the boat until he was at least temporarily stabilized. Five minutes. Ten minutes. Fifteen. At 20 minutes I called them back.
“We’re still on hold with Poison Control,” the owner said. “I think you should head over here now,” I replied. He could continue to hold for the toxicologist on his cellphone while driving. I gave my address. “Where are you coming from?” I asked so I would know how soon to expect them. “Fairborn,” he said. Fairborn? Is there a neighborhood somewhere on the Island called Fairborn? I wondered. I tried again. “What town are you coming from?” “Fairborn,” he replied a little testily.
I paused, then asked very slowly, “Are you on Martha’s Vineyard?” Nope. They were nowhere near the Vineyard. They had never even been to the Vineyard. Well, that’s odd. I exhaled and relaxed a little. I wasn’t going to have to deal with this potentially serious emergency, but Jack still needed medical care. We ended the conversation quickly so his owner could find an emergency veterinarian near Fairborn, wherever that was. How did this person get my phone number? What did he think when I kept talking about the ferry?
The next morning I couldn’t contain my curiosity. I called the owner back. Jack was fine. The toxicologists had determined the xylitol dose ingested was low enough to rule out liver damage, and that home monitoring for signs of hypoglycemia was adequate. They had advised feeding him every few hours overnight. We had a lovely chat. Jack’s owner, Aaron, had been completely bewildered the night before by my constant references to ferries, party boats, and islands. “I thought it was some weird kind of vet lingo,” he laughed. They were in Fairborn, Ohio, a few miles down the road from Antioch College, my alma mater. In fact, small world, Aaron’s girlfriend also graduated from Antioch, just two years ago. How did they get my number? A bizarre mix-up between an Ohio animal hospital and one on the Vineyard with a similar name, exacerbated by a mistake by an answering service. Happily, no harm done. After his gum-eating trick, Jack got extra treats overnight to keep his blood sugar stable, and I got to go to bed on time.