ThundershirtClassic Cat Anxiety Jacket, Heather Gray, Medium (9 to 13 lbs), THU-009

My cat Lewis is a big boy; we just went to the vet recently, and he measured in at 16 lbs.We just adopted a kitten, and Lewis was not happy about it. He is already a menace to our other cat, and the only thing that has worked historically is Prozac, which I was not excited about restarting due to side effects and the daily maintenance (Lewis hates pill pockets). Being so large, he definitely has a size advantage on the kitten, and I really wanted the kitten to feel safe in our apartment without having to separate them.When I was younger, our family dogs were scared of fireworks, and they wore Thundershirts to tremendous effect. The way Lewis was behaving made me curious about potential solutions to aggression and anxiety, and I came across people talking about how the Thundershirt helped calm their cat, and decided to give it a try.Lewis LOVES his Thundershirt. He protested me putting it on him the first few times, but the effect was IMMEDIATE. He went from stalking the other cats to cuddled up on the couch within minutes. He's never been particularly affectionate beyond rubbing up on your legs, but in his Thundershirt he will climb up in your lap and purr -- something I've NEVER encountered in the six years we've been together. His movement is slightly restricted, and especially at first there were some growing pains as I had to learn how tightly to bind the elastic-y straps that secure with velcro, but today he walks (very deliberately and slowly) with dignified and normal form. He doesn't complain when you put it on him anymore, so long as you don't pull too tightly on the straps. His demeanor is instantly calmer when he's wearing the Thundershirt, and he is far less interested in picking fights.We haven't tried a car ride yet, with which Lewis has always struggled with anxiety, but I have high hopes.The shirt itself is high quality, and my biggest gripe is that it holds on to the loose cat hair, which I don't think can be helped. It might also be to the benefit of the garment, holding onto his smell? It feels very sturdy, and I fully expect that it will survive at least 6 months, hopefully a year of near-daily use. I have not washed it in the washing machine yet, and haven't needed to-- he's got plenty of room to use the bathroom unimpeded, and it can be easily spot-cleaned of dust, etc with a damp rag.TLDR: I would definitely recommend the Thundershirt to anyone who's cat struggles with anxiety or aggression or some combination thereof. Lewis loves his!To the manufacturer: now that I know he likes it, I would definitely pay a $10 or so premium to get assorted fabric patterns and colors. Just saying! :)

I've been skeptical of thundershirts for years, especially for cats. But when I caught this one on sale, I decided to experiment -- fully intending to return it if I did not see results. I expected nothing to happen and my 15-pound male kitty to hate it. I was not going to get my hopes up.Well, I admit when I'm wrong. And this time, for my kitty, I have been wrong so far.I experimented with the shirt for a few days. He didn't like having it put on, and did not like moving around in it (he walked low, belly close to the ground) and seemed generally displeased.But then he laid down next to me on the couch and flexed his paws, purring. He stayed that way for a while.The next day, he still was unhappy getting it on and moving around in it, but eventually laid in his bed, and later mine, and was content and calm.I should say now, I did not purchase this for regular use around the house, but rather for travel. I wanted to see if it lived up to the hype and I could avoid the light sedation I had had to use in the past for hours-long road trips or flights.The true test came on a 6-hour drive and return trip. I put the shirt on him, which he still does not love, put him in his carrier and buckled it in for the drive. He was quiet, calm and relaxed the entire trip. Even when sedated, he sometimes meows or shuffles anxiously in his carrier. None of that this time. And when we arrived at our destination, he had none of the grogginess or disorientation that can come with sedation. He was perfectly alert and ate/drank/used his litter box normally.It was much the same on the return trip. He relaxed on his side and was perfectly alert, or napped, the entire 6 hours. He's used to traveling but has never done so well.Maybe it's a coincidence. Maybe not. This was just one road trip for us, but based on the results I saw, it was worth the price I paid (when I caught the shirt on sale).I purchased the large cat size and it fit my guy with room to spare. It's made of relatively soft, slightly stretchy material. I am a little concerned that the stitching will not hold up overtime. It's not reinforced and the material is not very thick, so durability is a bit in question. It's not the easiest to get on/off because of all the velcro, but once on, it is secure.I was also concerned with it being so snug and becoming uncomfortable for him, but he displayed no signs of discomfort or distress beyond initially having it put on. I doubt that will ever change, though.So take this all with a grain of salt -- all cats are different and what works for one will not work for another. But this worked for us and I'm happy with my purchase. I would recommend other cat owners give it a try, so long as you check ahead of time and know whether or not you can return it if it does not work for you.UPDATE: After two years of using this thunder shirt for my kitty, mostly for long road trips (think 5+ hours), I still highly recommend it for all the reasons I listed, it still works just as well as I described and it has held up over time. Again, every cat is different but I highly recommend this shirt. I’m even considering purchasing a backup.