Be forewarned that Dr Petr Bocek is not a great allergist as it claims. He did not even bother to examine me after reviewing my medical documents. He recommended me to have a MRI on my sinus area. Good thing I did not listen to him and went to Casey Institute. Dr. Melissa Clark who had a degree in internal medicine using Holistic approach. She saved my life by identifying the problem. My advice is to see a holistic practitioner if you have chronic rhino-sinusitis/allergies. He is not right a dr.