Yoga mudras do work. It is very beneficial for the health and balance of both mind and body. Mudras have been part of ancient Indian culture and are commonly used in traditional dance forms of India like Bharatanatyam, Kathakali, Mohiniyattam and so on.
Mudra yoga is effective and I have had experiences of cure for sleeplessness, stress, anxiety, diabetes and so on. Until recently, I was the full time caregiver to my late mother in law who was a dementia patient. Mudras helped to alleviate stress and related issues. People may think that it is a silly practice but I can assure you that it does work and although I will not advice not to go to a doctor, mudras can lesson the illness and pave the road to recovery.