Veterinarians Diamond Bar

Our mission is to make a difference in the lives of pets and the people who love them. Our belief is that clients and their pets should always be treated with compassion, dignity, and respect. They are the core of our existence and will forever be our focus.

Helping Pets since 1981


Dr. Patricia Colley, DVM, MPVM
Dr Patricia Colley, DVM, MPVM
I always wanted to be a veterinarian, but I hated high school chemistry and biology, and math, and trigonometry. So in college, I chose the business path and obtained a degree in Agriculture Business Management, which led me to banking. But banking was not my first love, so ten years later, with the help of a very supportive husband, I went back to school to study chemistry, biology, trigonometry and physics—and it turned out I enjoyed them all! I was accepted at UC Davis in 1992, and graduated in 1996—I was the oldest student in my class!

I became a veterinarian because I have always loved animals—this is why I do what I do. My love for animals compels me try to relieve their suffering, to heal their wounds, to assuage their pain, to calm their fears, and to comfort their owners when death is near. It all boils down to love—love for animals and love for people. My dad always seemed to be able to spot an animal in distress. One Sunday afternoon, coming back from a drive in the mountains, we saw a lost dog running frantically alongside the road. My dad pulled to car over, opened the door and the dog gratefully jumped in the front seat! (We were in the back seat.) We took him home, gave him water and food, and tried to find his owner. But he was abandoned, so he became our dog.

I am a Los Angeles County city girl who grew up with cats, dogs and a sister. We both enjoy ballet, tap and horseback riding. I have a Toy Poodle who can crawl on her belly like a commando; a Malti-Poo whose nick-name is "Eggy-Lift-His-Leggy" because he likes to pee on things; and a rescue cat who had her collar grown into her leg, but she is fine now! My hobbies are much more humble: yoga, reading about history and hunting for the good find at thrift stores.

I am very grateful for the wonderful opportunities I've had in veterinary medicine:
  1. My internship at Animal Specialty Group in Los Angeles. It is a first-class specialty hospital and I learned first-class veterinary medicine.
  2. My Master's degree in

    Veterinary Preventive Medicine

    (MDVM). My paper on the elemental composition of cat teeth with and without odontoclastic resorptive lesions was published in the prestigious American Journal of Veterinary Research in 2002.
  3. My Don Low Fellowship in Small Animal Anesthesia. This is one of several post-graduate Fellowships at UC Davis, and enriched my knowledge of anesthesia in daily arctic. I also took that information and instructed my students at Western Career College (now Carrington College).
  4. My position as medical director of Kitten Central of Placer County. This is an amazing organization of volunteers who rescue and save neonatal kittens using UC Davis Shelter medicine protocols, they de-worm, de-mite, and de-ringworm these babies. When they're old enough they get them "fixed" and back to their sponsoring organization, where they are adopted to their forever home.
I love many things about my job. I like getting to know our clients and their pets, and to help strengthen their human-animal bond. I enjoy problem solving—whether it's the problem of itchy skin or ear infection or diagnosing the cause of a lameness. I love creating a balanced anesthesia/pain management plan for each of our patients, to help get them safely through their procedure, and back on the road to recovery. I also enjoy dentistry, and strive to improve the dental health of our cat and dog patients. And I love learning new things at continuing education that I can take back into daily practice, especially cats and dogs to have a more enjoyable veterinary visit using Fear-Free® techniques.

My favorite case was the lovely Boxer whose owners saw her eat a dead rat that had been poisoned with rat bait. They brought her in immediately; I induced vomiting, and up came her breakfast along with the dead rat - one piece! (Dogs throw up the coolest things: a whole dead rat; half a chocolate cake; ear plugs; a bag of Hershey's Kisses - wrappers and all. The most gratifying is freshly eaten rat-bait—the poison is out of their system, and with Vit K, and activated charcoal, they'll live.)

Dr. Karen Smolen, DVM
Dr Karen Smolen, DVM
Ever since I was a child I was fascinated with the lives and health of animals. I could never have enough pets. This includes dogs, cats, and many different species of parrots. The day I graduated Veterinary Medical School I shouted, "I did it!". Dream come true! I went to Ross University, College of Veterinary Medicine. The first three academic years were on St. Kitts in the Caribbean. My Senior Clinics were at Oklahoma State University College of Veterinary Medicine.

I grew up on Long Island in New York where my influences were the amazing veterinarians I got to know through bringing my pets to. The most incredible, and endearing life changing event was birthing a calf in veterinary school. I brought a baby animal into this world. It was suckling on my hand immediately. Wow! How incredible.

I love surgery. I love to work with my hands, and enjoy the gratification of helping heal an animal with surgical skills.

Bruce is my 11 year old Cavalier Spaniel. If you stop petting him he will keep tapping you with his paw. My newest editions are a beautiful little Brussels Griffon puppy named Harper. What a sweet happy soul, and my new Caique parrot named Olive. What a little clown. She rolls around for laughs, loves her toys and loves to give kisses.

I have been a drummer since I was thirteen years old. Artwork, including much animal art, is my next passion. Finally I love to get on my Harley Davidson motorcycle and ride with the wind.

Dr. Charles Mintzer, DVM
Dr Charles Mintzer, DVM
By the time Charles Mintzer was 10 years old, he was already known as the neighborhood

animal caretaker.

Growing up in a small Queens, New York apartment, Charles often walked neighbors’ pets and was always concerned about their health. In his own home, Charles kept non-traditional pets such as chameleons, garden snakes, a myna bird, and a baby chick that somehow grew into a raucous rooster. Following a family trip to Florida, Charles even found himself with a baby alligator. Young Charles’ affinity for animals continued throughout his life, providing him with a wonderful foundation for his veterinary career!

Growing up with his mother and older sister, Charles enjoyed playing roller hockey, football, and stick-ball. He competed in Little League baseball until age 10, when he realized that he didn’t have the talent to succeed as a professional baseball player. Once he abandoned that goal, Charles happily focused on becoming a veterinarian, and enjoyed his mother’s lifelong support for his career choice.

During Charles’ high school years, he participated in a program for students who planned to become veterinarians. For two summers, Charles worked on dairy farms in upstate New York. Next, he enrolled in Cornell University’s undergraduate program, and worked in animal hospitals during his summers. In 1978, Charles graduated from the Cornell University College of Veterinary medicine. By that time, Charles was ready for a change of climate, and happily moved to warm, sunny southern California.

After purchasing and growing his own veterinary practice, Dr. Mintzer combined his efforts with Dr. Beighlie in 2008. After both practices were merged, the new All Pets Medical and Surgical Center offered more sophisticated technology and expanded treatment options. In particular, Dr. Mintzer is intrigued by veterinary dermatology; and he has been fortunate to receive additional training from recognized dermatology specialists.

Dr. Mintzer has also become knowledgeable about veterinary dentistry, and has concerns about the potentially severe impacts of poor dental care on an animal’s overall health. He very much wants to focus on dental disease prevention, as the problems are often far advanced by the time his clients notice any symptoms.

While Dr. Mintzer appreciates the technology and treatments at his command, he always focuses on the profound human-animal bond at the heart of his clients’ relationships with their pets. His first dog Angel, a beautiful golden retriever who enriched the entire family’s life, taught him the life-changing importance of that relationship.

When Dr. Mintzer’s away from the hospital, he enjoys life with his wife Leslie. He’s also an energetic ice hockey player, and his team has won the league championship several times in the past few years. The couple’s son is currently a junior in college; and he enjoys playing a few rounds of golf with his father during breaks from school. The couple’s fourth-grade daughter is an active young lady who enjoys sports, dancing, and singing in the choir.

Finally, the Mintzer home has a well-balanced complement of furry family members. Carson the Chihuahua loves to relax on the Lazy Boy recliner with Dr. Mintzer’s mother, who also lives with the family. Mowgli the French bulldog is a people magnet who loves everyone. In contrast, the family’s two cats, Crookshanks and Sauly, have adopted their own agenda. These two independent felines believe they belong at the top of the household pecking order.

Dr. Damon Goldstein, DVM, Diplomate ABVP, Our Founder
Dr Damon Goldstein, DVM
Dr Goldstein is the founder of the practice in 1981. With a life-long passion to help dogs and cats and a dedication to deliver superior, multi-disciplinary

veterinary care.

He built his practice on the belief that clients and their pets always be treated with compassion, dignity and respect.

Dr. Goldstein graduated from Cornell University Veterinary College in 1972. He is a Board Certified Specialist in Canine and Feline Practice. Becoming a Board Certified Specialist entails a very rigorous course of additional studies and examinations. In addition, Diplomates must prepare and re-certify in their specialty every ten years. He has the distinction and status of earning a Professional Certification from the American Board of Veterinary Practitioners. In fact, Dr. Goldstein is one of only 900 ABVP Diplomates in the United States and abroad. He is dedicated to deliver superior, comprehensive, multi-disciplinary veterinary service to cats and dogs.

Dr. Goldstein is a member of prestigious local and national veterinary organizations, including the American Veterinary Medical Association, the California Veterinary Medical Association, the Southern California Veterinary Medical Association, Accreditation for the USDA’s Animal and Plant Health Inspection Service and the American Animal Hospital Association. He is a founding director of the East Valley Emergency Pet Clinic in Diamond Bar and the Inland Valley Veterinary Specialist and Emergency in Upland.


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