We have five of our own chihuahuas and one foster chihuahua, each one has a problem with collapsing trachea or reverse sneeze. My littlest one 4.7 lbs has the trachea problem and when it happens I just keep calm and hold her to calm her down. If they continue to gasp for air they get further excited and is harder for them to recover quickly. Just keep calm and keep them calm. Her attacks are fewer and not as long. One foster chi that we ended up adding to our family was 20 lbs when he first came to me as a foster, it took one and a half years but he is now 9.5 lbs. They are on a strict food and snack every day where they are watched that they don't invade others food.