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After rescuing my dog Roxie, I quickly realized I had a fearful dog who needed some serious help. Fear of the vet, separation anxiety, leash reactivity, and just dealing with daily life in general are only some of the things Dr. Sinn has helped us with. She developed a plan for my family to work with Roxie at home  and out and about, and made it all easy to follow and understand.  Always kind and compassionate, Dr. Sinn was there for us every step of the way. I now have a happy and fun member of the family who I wouldn’t trade the world for. I can’t recommend Dr. Sinn enough!

--- Susan Comstock



Dr. Sinn created peace and tranquility in our house! Berta, our dog, often attacked our older dog. After seeing Dr. Sinn, we have not had a single dog fight and our older dog has returned to her playful nature. Our visit went beyond our expectations when Dr. Sinn also helped us with numerous other behavioral issues that we had learned to live with – over excitement, resource guarding and aggression.  Berta has evolved into a wonderful dog!

--- Dottie Swanson

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Dr. Sinn is wonderful to work with!  She has helped my reactive dog tremendously, addressing his issues from both a behavioral and pharmaceutical perspective.  During our first visit, she spent a lot of time listening and observing before coming up with a plan.  We worked together to determine what was making a difference and what needed to be tweaked.  She is always available and responsive when I have a question or see a change in behavior.  As a result, Jeter is happier and more able to deal with day to day stress. He has been able to work and show around distractions.  Jeter and I would highly recommend Dr. Sinn!


--- Nancy Kurkjian

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   Dr Sinn attended the LCEA Expo where I met her and became interested in the services and solutions she provides.  I have a three year old Quarter Horse mare that had a bad trailering experience, and consequently I was unable to get her to load onto my horse trailer.  I have owned horses for almost 50 years and this was the first time I had been unable to get a horse on a horse trailer.  All traditional methods had failed, and my main concern was that neither the horse nor I be injured.
   Dr Sinn made a house call to meet "Sparkle" and to evaluate her health and behavior.  We discussed several behavior modification techniques, which were simple, safe and easy to understand.  Over the course of several weeks I worked regularly with Sparkle to adjust her attitude and behavior toward the trailer, using positive reinforcement.  I can report the process was a complete success!  Sparkle has been on several outings now, loading quietly and safely.  
Thank you Dr. Sinn!

--- Stephanie Jennings,

LCEA Board Member

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Dr. Sinn changed my little girl's life! Biscotti, a 4 y.o. Samoyed, always was a little nervous about certain things like windshield wipers, some strangers, and loud or chaotic environments, and a bit anxious when left alone. She would bark in her crate for a few minutes when we left, but settled down in a few minutes. She was able to cope with this stress until one of her older brothers (dogs) passed away. All of a sudden, the separation anxiety became worse, and she would pace, spin, bark and dig at her crate for hours. Seeing a beloved pet like this is heart breaking. The stress was no longer tolerable and was making both of us miserable.

With Dr. Sinn's help, we created a medication and training plan to help her, and now she is calm and relaxed in her crate when we leave, and still sleeping or calmly watching the world when we return home. Dr. Sinn listened to my concerns with compassion and patience and took the time to answer all of my questions about her treatment plan. She followed up with written instructions promptly to make sure I had all the information I needed to confidently address Biscotti's issues. Dr. Sinn is professional in her handling of animals and ensures the animal is as comfortable as possible during the visit. We appreciate her knowledge, and continuing pursuit of education to make life better for her clients. Biscotti is a much happier and relaxed dog now than she was 9 months ago thanks to Dr. Sinn.

--- Lisa Marino

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Loudoun County Animal Services reached out to Dr. Sinn for consultation on a particularly challenging cat.  As Loudoun’s only Veterinary Behaviorist, we knew if anyone could help – it was Dr. Sinn! 

Lightning was brought to the shelter because his owners were no longer able to care for him.  Almost immediately the stress of the shelter was too much for Lightning and he began to obsessively pluck his fur.  He was nearly bald when he was introduced to a wonderful LCAS foster family and Dr. Sinn.  Working together, they developed a stress management and medical intervention plan that worked wonders for Lightning!  He is now a happy, fully-furred cat living out his days with his an adoring, new adoptive family.  Thank you Dr. Sinn for so kindly and compassionately caring for Lightning!

--- Amy Martin
Shelter Operations Manager

Loudoun County Animal Services

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We were at our wit's end dealing with our fearful Cane Corso, Luna. We lived with constant anxiety not knowing what she would be afraid of and how she would respond to different people and pets. We refrained from taking her to many places and even minimized traveling ourselves. 


When we first approached Dr. Sinn, we had very real concerns that Luna might bite someone and be labeled dangerous. We were ashamed by her crazy behavior but Dr. Sinn was extremely patient and kind - praising the things we had done correctly, and helping guide us in a positive direction. With the help of some medication and training methods, Luna has become a different dog in the last year. The sweetness she reserved for a select few people before has now expanded to lots of new friends! We have taken several trips and Luna was fine with and without us. We are so very grateful for Dr. Sinn's help and expertise. 

---- Jamie Vail

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Our sweet elderly Cat-Cat had begun exhibiting signs of disorientation and confusion, and we had been unable to find any medical explanation for her erratic behaviors. We would find her wandering around the house with a toy, crying out as though she were lost. Additionally, she was attention seeking and often restless despite our best efforts to console her. She had even started waking us up throughout the night with these episodes. 


Dr. Sinn came to our house and spent lots of time observing Cat-Cat and evaluating her behavior. With her assessment, she formulated a comprehensive treatment plan. Dr. Sinn researched several dietary options, medications, toys and supplements for us to try. We have been so pleased with Cat-Cat's improvements and her quality of life is dramatically improved (as well as ours!). 


--- Jamie Vail

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When I initially contacted Dr. Sinn about Tango, I was delighted at her quick response and obvious desire to help us.  Tango was highly reactive to everything; people, dogs, cats, squirrels, deer – basically anything that moved.  His response was uncontrollable barking and lunging episodes.  In addition, Tango was a resource guarder.  He was highly sensitive to touch; especially his feet, tail and ears. 

Upon initial evaluation, Dr. Sinn recommended medications and a training plan for Tango.  The change in Tango by our next meeting was heartwarming.  Outside, Tango approached Dr. Sinn in a controlled fashion.  Tango then took some meat from Dr. Sinn’s hand.  It was AMAZING!!!  A totally different dog from the first time we met.

Today, Tango does not bark and lunge at people in other cars like he used to do.  For short periods, he allows me to clean his ears, he gives me his paws and he stands quietly when I have to handle his tail.  He does much better with the neighbor dogs; he looks and may let out one bark or nothing at all.  We continue to work with him and realize that this is a journey.

Dr. Sinn is a compassionate professional who changed all of our lives forever.  Her love of her work and of her patients is evident.  Her follow-ups were detailed and she always had kind words of encouragement for our progress.  Many thanks to Dr. Sinn, for providing us everything we needed to help Tango live a happier life and for bringing joy to all three of us.  

--- Mark and Janice Barnhart 



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When I come home and discover that my dog, Flim-Flam, has shredded cardboard boxes in my absence, I bless Dr. Leslie Sinn’s name!

Crazy, you ask?

No … actually it’s fabulous, but more about that later.

Dr. Sinn a skilled and highly-trained veterinary behaviorist who has worked with us to develop a balance of medications to help my shepherd mix with his pronounced fear of thunderstorms. She is also a Certified Professional Dog Trainer who offers guidance for management and training to address the emotions and behavior surrounding his fears.

When he was about a year and a half old, Flim-Flam began to show concern during thunderstorms. Simply feeding him spray cheese every time he heard a thunderclap helped minimize his distress for a year or two. The Fourth of July was more troubling with hours of non-stop explosions followed by unpredictable random fireworks set off by neighbors, and he was increasingly concerned if I were absent during a storm, destroying molding, pulling electrical outlets off the wall, and eating ethernet cables. Xanax prescribed by our general practice vet provided relief for a time again, but side effects (loss of coordination and grogginess made it clear that we needed to make adjustments.

Dr. Sinn worked with us to blend medication and behavior modification to lower Flim’s anxiety during storms and other loud sound events, and she identified an underlying generalized anxiety that plays into his sound phobias. She provided phone and email support after the initial assessment, proactively checking in to see how things were progressing. She prescribed and adjusted daily medications carefully to find the “sweet spot” where they alleviate his anxiety without side effects, and she continues to provide support as concerns arise. From start to finish I have been struck by what an effective listener she is, and by how seriously she addresses concerns of quality of life for both dog and handler.

At this point Flim will occasionally sleep through a thunderstorm without additional medication—unthinkable even a year ago. His level of distress during storms or fireworks even when worried is considerably reduced. He can think, play training games, and chill out in most rooms of the house.

…and the shredded boxes?

Even with his dramatic improvement, Flim-Flam will still occasionally panic if I am away during thunder or fireworks. He relieves his stress by shredding—an activity which has included shower curtains, the occasional dust ruffle, and a bit of moulding from time to time. It was Dr. Sinn’s inspiration to provide appropriate shredding items in strategic locations if there is a chance of thunder when I go out. Cardboard boxes nested within one another, stuffed with office paper, have been an excellent solution. Flim can relieve his stress, and no furniture repairs or replacements are required!

Leslie Sinn is a skilled doctor, a thoughtful counselor, and a gifted trainer. If your dog is struggling with serious behavioral issues she will give you and your best friend excellent care.

--- Marnie Montgomery 

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At the suggestion of our local vet, I sought help from Dr. Sinn for our rescued 80 pound treeing walker coonhound, Jake, immediately after Jake expressed aggression toward my 7 year old son inside the house.  Jake had been with my family for about six months following his adoption when he started to show alarming behaviors. His guarding of the family sofa revealed itself through Jake growling at family members napping there.  Soon after, Jake hunted and stalked the 7 year old with aggressive chasing, herding, and baying to the extent that the dog would not leave the child alone.  My son--who loves the dog--was reduced to fleeing to his own room where he was crying in fear, terrified to come out. That night I thought I might need to call animal control on my own dog. But we got through it, and I credit Dr. Sinn in helping to  save Jake's very life. The prospect of Jake being successfully adopted after showing aggression on top of his cancerous tumors and Lyme disease struck me as low, so we were motivated to try our hardest to help Jake. The entire family voted to try.


With Dr. Sinn's help, we have worked to use positive techniques to modify and manage Jake's behavior.  We worked with a trainer Dr. Sinn recommended, and we learned to recognize and avoid triggers that cause Jake's extreme anxiety to spike. Dr. Sinn helped train us as the dog caretakers as much as she changed Jake. Jake now seeks out the attention of the 7 year old and has stopped guarding the family sofa. The dog is doing well walking in crowded public venues, seeking out strangers to pet him in some cases. He has favorite dog buddies in the neighborhood, and seemed to enjoy new caretakers to the point that he gave a goodbye to each at the conclusion of a recent short kennel stay. We are in a much different and better place with Jake than we found ourselves in six months ago--a much happier ending than I expected.  Thank you, Dr. Sinn!

--- Tania O.

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Philly was 4.5 months old when we adopted her from a rescue group. It was clear from the beginning that she had severe fear issues and was especially afraid of men, particularly my husband Perry.  We had been to several different trainers without success.  We started seeing a new veterinarian in early 2017 and she quickly referred us to Dr. Sinn.  By now Philly was 2 years old and really no better with her fear issues.  She growled, barked and ran to a different room when Perry entered our house, or moved room to room.  She paced and scanned him constantly, and he could not participate in her care.  Additionally she was fearful of other unfamiliar people, particularly men.  


As we sat in Dr. Sinn’s office, Philly crouched in the corner behind me.  Dr. Sinn identified every behavior Philly exhibited within 5 minutes of meeting her.  She was honest with us, and helped us set simple goals for Philly.  She started Philly on a course of medication and gave us instructions on handling interactions between Philly and Perry.


With Dr. Sinn’s guidance, we titrated and added medications.  We kept up with the “treat sessions.”  A year and a half has passed and Philly has made great progress.  At 3.5 years old she spends less time in fear and more time as a “normal” dog.  She is more relaxed in the same room with Perry.  She lines up for her “treat session” without prompting and sometimes when it isn’t even “treat time.”  She is more at ease with new people in general.  She even tolerates Perry holding her leash on a walk!  


Dr. Sinn has rejoiced with us and Philly's progress and comforts us when she has a (now more occasional) setback.  Philly will always be a work in progress, but I would hate to think what our lives (and Philly’s life) would be like if we had not met Dr. Sinn.  She has literally been a lifesaver!

--- Joanne and Perry Smith

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At the age of 9 months, Tux began to exhibit new and strange behaviors.  People (including his human dad), places, and things that never bothered him before would cause him to bark, growl, and constantly pace around.  When Tux was asked to leave day care because he was acting aggressively and biting other dogs, we knew we had to take action.  We started working him with trainers that had different methods and could never find one that helped long term; Tux’s behavior continued to cause concern…what would he do next and to whom? 


Our regular vet diagnosed Tux with ‘fear anxiety’ – any time he became afraid of something or someone, he would act aggressively.  After starting some medication, it wasn’t long before we determined that he needed additional help by someone with an expertise in canine behavior.  Dr. Sinn was able to determine what was happening with Tux after only one visit!  She added some daily meds and helped us understand what was happening to him and why he was reacting the way he was.  We were educated to see the warning signs and learn what our solutions should be which is  just as valuable as the medication.  Dr. Sinn helped us greatly to obtain some normalcy in our lives, especially Tux, and we would definitely recommend her and her team to anyone who has a beloved pet with anxiety issues.

--- Jennilynne & Mike

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Our rescue pup, Lupo, had fear issues from the very start. Loud noises? Check.  Strangers?  Check.  Outside? Yes, outside.  If he lost sight of the front door of our house, he would freeze.  Counter conditioning didn’t work since he was too afraid to take, even the highest value, treats.  At that point we knew we needed help.   Dr. Sinn was amazing.  She and her staff were kind, patient and gentle.  My emails were always answered within 24 hours in a complete and thorough way.  She was happy to work with our trainer on developing a plan for Lupo (and us).


A combination of medication, nutritional supplements, training, and environmental control have made the world of difference.  We have a loving and happy dog.  He still doesn’t like trash days.  Those trucks are big and loud! But he will walk around our neighborhood or a neighborhood park quite happily.  With support from Dr. Sinn we successfully managed a multi-state move without issue. 


Prior to our first appointment, Dr. Sinn asked us what our goal was for Lupo.  Yes, there was a time where I imagined a dog that would sit our feet while we ate dinner at outdoor cafes, or would walk happily around a farmer’s market with me on a Sunday but that question made us stop and think.  All we really wanted was for Lupo to see the world as a less scary place.  Nearly two years later, it truly does warm my heart, to share that we have met that goal.  We could not have done it our own and are deeply grateful to Dr. Sinn and her practice for helping us help a dog we love a lot.

--- Alison

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I rescued Oberon, a miniature schnauzer, when he was two years old.  While he settled in well with me, it became apparent he had some behavioral issues due to fear aggression.  His issues are particularly profound when any person other than me would come to the house. I enlisted an in-home dog trainer in an attempt to address the problem and, while it was helpful in controlling some of the behavior, it did nothing in terms of actually alleviating his fear aggression or not seeing any others as a threat.  This became particularly frustrating and upsetting when I started dating someone and having them over. I realized the training techniques would not be enough for him and sought out Dr. Sinn’s expertise.  


With Dr. Sinn’s help, it became apparent that at such a high level of anxiety, he would never be desensitized or used to a new person in his home.  Dr. Sinn was able to offer training advice that was more conducive to an anxious dog (some of the training techniques I learned previously were actually contributing to his stress) while prescribing Oberon medication to reduce his level of anxiety.  It was also cathartic for me to be able to talk to someone that understands the frustration and nuance of having a fear aggressive dog. After a couple of months adjusting to his new medication and using the new techniques, a switch was flipped and Oberon welcomed my now-wife with open arms!  While Oberon still has fear aggression issues, his life is a little bigger now, he’s more manageable, and he has more love in his life. This “small” but absolutely life changing win with Oberon was absolutely worth enlisting the help of Dr. Sinn.

--- Megan

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