Asthma, anxiety, and panic all go hand in hand, so it’s no surprise that your father is still apprehensive despite getting his asthma under control. It’s important to remind him that there are ways to cope with an asthma attack including an inhaler, controlled breathing, and meditation. It also might be helpful to have your father talk to a trained professional about the anxiety he experiences. It often helps to talk about the situation outloud to help address a person's fear and anxiety.