COVID-19 Response
In order to reduce the impact of COVID-19 for everyone, and for us to be able to continue to provide this essential service for your cats, we’ve modified our services for now, and ask for your help.
At the time of your appointment, we will admit your cat from the parking lot without your coming into our hospital too. We’ll send you an email that details our precautions when you schedule.
Offering the safest, most reliable treatment for Feline Hyperthyroidism

Hyperthyroidism is the most common hormonal disease of cats resulting from excess thyroid hormone, which puts significant and potentially fatal stresses on the body. Radioiodine therapy is the safest and most effective therapy available. It's less risky than surgery and doesn't require medicating your cat daily for years. Most cats stay a couple nights before returning home — happy and healthy.
Essential Reading (before your appointment):
- Making an Appointment
- Cost of Treatment
- The Hospital Stay
- Post-Treatment Guidelines
- Cancellation Policy
- Please read if your cat’s T4 level is 12-19 µg/dl: Understanding Your Cat's Semi-Aggressive Hyperthyroidism
- Please read if you cat’s T4 level is greater than 19 µg/dl: Understanding Your Cat’s Aggressive Hyperthyroidism
Testimonials
My cat was diagnosed as hyperthyroid when she was 10. We had her treated as soon as she was diagnosed and I was glad it was found early. I didn’t really give the thyroid... read more
SavannahLynnwood, WA
Pox's Story Does it make sense to treat hyperthyroid in a fourteen-year-old, mostly outdoor cat? That’s what we were asking ourselves in the summer of 2013. Pox let me know his opinion by following me... read more
PoxSeattle, WA
Great place. They were so good to my kitty who was really scared. He seems to be completely cured. read more
Thanks to Dr Faythe Vaughan, and her kind staff in Shoreline and Tacoma for giving us at least 5 extra, good quality, years with our buddy, Rocky! He was a rescue cat to begin with, and his good... read more
RockyTacoma, WA
My family has had Lila since she was a kitten. She is turning 15 in October, I was only 10 when we got her. I moved away as an adult for a few years... read more
LilaShoreline, WA
You took care of our Nina Kitty and it was like she found the Fountain of Youth! At age twelve, she had been slowly losing weight and getting a bit more "yowly" but we... read more
NinaMy family has had Lila since she was a kitten. She is turning 15 in October, I was only 10 when we got her. I moved away as an adult for a few years... read more
LilaShoreline,
We want to thank you for your extraordinary efforts in looking after our Samson's well being. You took the initiative of a problem we were not aware was even present. We are very, very... read more
SamsonPort Townsend, WA
Three months ago my 13 year old kitty Miss Fanny spent three days in the care of Dr. Vaughan and the staff. Before treatment she had been losing weight, getting more lethargic and her... read more
Miss FannyNorthbend, WA
Monty is 12 years old. Dr. Vaughan had been monitoring Monty’s thyroid over the years and identified that he was borderline for hyperthyroidism. After discussing his overall appearance, behavior and appetite, we decided that... read more
MontyAs a member of an animal rescue organization on Vashon Island (VIPP), as well as being a chronic cat owner, I've had many opportunities to visit the Feline Hyperthyroid Treatment Center. Over the past... read more
Piro Kramar. Vashon Island Pet ProtectorsVashon Island, WA
I wanted to drop you and everyone at FHTC a note to let you know that Byron (the PAWS™ kitty FHTC treated pro bono earlier this year) was adopted last month! Even better, he... read more
ByronSeattle, WA
They are very personable, professional, and knowledgeable about their very specialized practice. If you have a cat with thyroid issues, I highly recommend this clinic. read more
BeckySeattle, WA
Will & Grace found me in 1999 when they were four weeks old. They were born near in a parking lot off Highway 99. They are twins and do everything together. This year they celebrated their... read more
Will, Grace, and HunterEdmonds, WA