As you mentioned the phlegm coming from your head into your throat, this sounds like post-nasal drip. Homeopathic remedies may be able to help and I strongly recommend it. There are no adverse effects if it doesn't work as it's a form of energetic or vibrational medicine. Which remedy will really depend on your specific symptoms and other factors or signs, such as what colour your phlegm is. For example, if it the secretions are more thick and ropy, then the homeopathic remedy Hydrastis Canadensis 30c might help. Taking one unit, or pilule, once daily for 7 days and then reviewing might be one way to approach post-nasal drip. As you mentioned not having a sore throat or cough, it might I recommend finding a good local homeopathy if possible - if not, it is possible to book one online. Steam inhalation may also be beneficial. Take good care and wishing you a speedy recovery! You mentioned your doctors, holistic and not holistic, cannot figure out how to resolve it. There might be other energetic and lifestyle reasons contributing to post-nasal drip, such as environmental or dietary factors. I have experienced and successfully reversed or cured post-nasal drip for myself and can help further. If you have any follow-up questions, call me.