VetOne - CrossBlock II™ Kills & Prevents Fleas on Cats (Over 8 Weeks Old) | Waterproof to Last Long | Ensures 3 Months of Protection (9lbs+)

Got rid of all fleas within a week

Only lasts 3 weeks or so but it works

UPDATE; OK, it's now 8 days since treatment was applied. The cat last night "Stayed" in his doghouse. This morning, he came in the house and was "Ravenous." He ate his regular cat food, like he hadn't eaten in a week (which he pretty much hadn't.) He also stopped the "Loud Meowing." After eating his cat food, he proceeded to go over and throw himself into his large doggie bed and go to sleep. We haven't seen any of this behavior for 8 days. So, I have to give one more star to my review. The cat seems to have returned to his "Pre-Hysterical" self. I would say, since this is such a "STRONG" medication and it is a poison, put a "Half Dose" on your cat, until you see how they react. We won't use it on this cat again. He had too strong of a reaction.Original ReviewApplied this to 9 pound cat 5 days ago. Since then, his personality has changed "completely." Not sure if this caused some kind of neurological problem or psychological problem. He's become a different cat. Before, he would be happy to sleep in his indoor pet bed and always loved his cat food (more than loved it.) He has a dog house on the front porch with blankets and his bedding and toys that he loves. You can nearly always find him there. He never meowed.Since we applied this flea medicine. He won't sleep in his indoor pet bed, he goes through the house meowing at the top of his lungs, he stands outside meowing loudly (you'd think we were murdering him), he will not go near his beloved doghouse, he won't eat and he won't stay in the house more than 3 or 4 minutes and then he has to get out. He used to have a patio chair he loved to lay on and he won't go near that. It snowed last night and he always goes into his doghouse when it's cold or comes into the house. We checked all through the night and he was nowhere to be found. He came back this morning, but wouldn't eat, so I fixed him some chicken. Normally, I wouldn't get him off his catfood, but he loves chicken and he has to eat something. He gobbled the chicken down, drank some water and then meowed frantically, again like he was being strangled. I let him out and he took off running in the snow, into the woods. We're hoping that whatever is going on, will wear off or the cat will come back to his senses. All the cats are rescue or feral cats and the other cats are looking at him like, "what is wrong with you?" But, they're backing off and giving him his space. We can only do the same. These kinds of cats have to pretty much do what they want. They're not like regular domestic housecats. He will allow my sister to pet him and she was able to get the flea medicine on him, but I can only feed him. He is still semi-feral.So, I can only report on what happened to this cat. This is a poison and some people have reported their cats losing hair, vomiting or being burned by it. Does it work on the fleas? Not sure, because cat won't stand still long enough to tell. I would not purchase it again & I do not recommend it. Thank you for reading my review.

I've been using Cross Block II for several years...ever since my veterinarian recommended it and even sells it in their clinic. They told me it's the same as Advantage II but less expensive. I have never had a problem with it and it has always worked very well. I don't always like using these insecticides on my cats but sometimes it's necessary. I have tried some natural products with good results too but sometimes the fleas are really bad, especially in the heat of the summer. This stuff always does the job.

For our cats, I put this on the same level of effectiveness as the much more expensive Advantage products, which we have tried extensively. I appreciate the lower price-point here & I plan to purchase more. The past few years in the Midwest have been ATROCIOUS for fleas & we've been at war with the beasts in our home during prime flea season, & this product definitely helped keep them at bay during late summer/early fall. Application is easy & not messy at all if done properly. Be certain to get as much as possible directly on the skin not the fur. Also be sure it's on the upper neck/back of the head area, as there is a good amount of liquid in these applicators & excess may be prone to run.We haven't seen but maybe a stray (but clearly struggling) flea or 2 on our kitties since application a couple weeks ago & they barely itch at all anymore. This makes everyone very happy.No this product is not as cheap as PetArmor, which we have also tried extensively, but it does the job MUCH better comparatively.Fyi our war on fleas was finally victorious after a multi-faceted approach involving 2 house-wide sprinklings of food-grade DE, which I left on for about a week, then swept, vacuumed & mopped up. But the huge table turner was the house-wide application of a Precor 2000 Plus aerosol spray, which includes both an instant flea killer & a long-term growth inhibitor, & it also dried pretty quickly as an added bonus. All of this combined w/ regular vacuuming & the use of this product on our kitties allowed us to get our particular situation completely under control.In short, highly recommend this mid-point cost alternative to much more expensive brands.

I have two cats and two dogs living in a southern state with a ton of fleas. I have also fostered cats before and I know first hand how bad fleas can get very fast. I and the organization have spent big bucks on flea meds. However, I saw some of this being sold at the humane society and looked it up. I ordered some to just try not expecting much of it. I was spending around $100 a month for our 4 pets and still would see some-even with the most expensive vet brands. Personally, this has worked the best and much less expensive. I refuse to use the $3 stuff from Walmart because it’s dangerous and does not work. However, I’m super skeptical and this works great. It has been what we used since. Like any other brand, make sure to keep your animals on the same RX cycle and do it consistently per the directions. I do comb mine with a flea brush also every few days. It’s hot here and my dogs go outside so they are prone to them. Great product!