ALBUQUERQUE, N.M. — Q: About six months ago, our 15-year-old Shih Tzu developed a new fear. We think he may have sundowner syndrome. Late afternoon, he starts stretching his head way out and sniffing the air like crazy. Shortly after the sniffing starts, he begins to tremble violently. This usually goes on for an hour, sniffing and shaking. He always was afraid of thunder and gunshots/fireworks, but now he is deaf. We find no specific item that triggers this fear.
Dr. Nichol: I’m sorry to learn of your Shih Tzu’s struggles. Older dogs, like elderly people, are at risk of dementia. The canine version, called cognitive dysfunction syndrome, or CDS, is nearly identical to Alzheimer’s disease. Despite internet chatter that dogs can have sundowner syndrome, no scientific support exists for afternoon/evening behavioral events.
There are a lot of fading canine seniors; 68% of dogs ages 14 to 16 suffer from CDS. Symptoms include confusion, pointless barking and aimless pacing. Some become less interested in their people, while other affected dogs get more clingy. They may be easily startled but sleep more deeply, especially during the day. Night waking is common. Dogs in later stages may house soil. In the end, these are heartbreakers. Like people with Alzheimer’s, nobody gets out alive.
Your dog’s late afternoon symptoms may be caused by CDS, but all other possible physical causes need to be considered before this diagnosis can be reached. A brain tumor (common in older dogs) could be at fault. And while moderate hearing loss is expected, complete deafness can also occur with a brain lesion.
Your boy needs to see his veterinarian for an exam and lab profile. The Animal Neurology and Imaging Center in Algodones can then pursue an in-depth neurologic evaluation plus an MRI of your dog’s brain. If nothing is identified, this older fellow can be treated for CDS.
Management methods for cognitive dysfunction syndrome in dogs have advanced significantly. Research-based diets, supplements, medications and behavioral therapies improve life for many old-timers – for a while. Your boy may have more good time left. I urge you to have his little head carefully examined.
Each week, Dr. Jeff Nichol makes a short video, blog or a Facebook Live to help bring out the best in pets. Sign up at no charge at drjeffnichol.com. Dr. Nichol treats behavior disorders at the Veterinary Emergency & Specialty Centers in Albuquerque and Santa Fe (505-792-5131). You can post pet questions at facebook.com/drjeffnichol or by mail to 4000 Montgomery NE, Albuquerque, NM 87109.