The causes of olfactory impairment may include colds, nasal sinus diseases, craniocerebral trauma, etc. The approach to restore the sense of smell needs to be based on the cause of the disease. 1. Colds: The loss of sense of smell caused by colds is mainly due to congestion of nasal mucosa, which leads to blockage of nasal passages, and it is necessary to use medicines such as Seroquel Hydrochloride and Budesonide under the guidance of doctors to ventilate the nasal passages, so as to make the sense of smell return to normal. 2. Nasal sinus disease: sinusitis, nasal polyps and other sinusitis often cause nasal congestion, inhaled gases are difficult to enter the olfactory region, resulting in olfactory disorders, can be prescribed the use of decongestants and glucocorticosteroids nasal sprays, such as Seroquel, hydroxymethazoline, Trimethoprim, budesonide and so on. Nasal polyps can be treated by surgery, and sinusitis can take clarithromycin. 3. Craniocerebral trauma: due to trauma to the cranium may lead to olfactory nerve damage, thus causing the loss of sense of smell, you can follow the doctor’s instructions oral vitamin B12, vitamin B1 and other nutritious nerve drugs, if the olfactory nerve function is completely lost, it is not easy to recover. If the function of the olfactory nerve is completely lost, it is not easy to restore the sense of smell. You should first go to the hospital to find out the cause of the olfactory disorder, and after clarifying the cause of the disease, you can take standardized medication and treatment under the guidance of the doctor.