At the beginning of a cold, there will be a lot of watery nasal discharge, which is similar to the symptoms of allergic rhinitis. However, after four or five days, the amount of nasal discharge decreases and gradually turns into yellow sticky nasal discharge. Then, unless the cold worsens into pneumonia or bronchitis, etc., this yellow mucous nasal discharge will stop at most after two weeks of the cold. However, in allergic rhinitis, there will be a large amount of watery nasal discharge as in the beginning of a cold, and the watery nasal discharge will not change even after a month. In the case of hay fever rhinitis, the same symptoms last for two or three months, and in the case of chronic allergic rhinitis with wall lice and dust as the cause, the symptoms do not disappear throughout the year. Therefore, if the nasal discharge is watery for three or four weeks, it should be presumed that the patient may have allergic rhinitis. In addition, apart from the change of nasal discharge, the correlation of other symptoms can also help to distinguish between cold and allergic rhinitis. Usually, a cold is accompanied by fever. After the first stage of runny nose, even if you do not have a fever, you may feel slightly hot, and you may feel tired and drowsy. Allergic rhinitis rarely causes systemic symptoms such as fever, but the main symptoms are concentrated in the nose or eyes, and allergic rhinitis may cause itching when the skin is exposed to pollen and other allergens. At the same time, the symptoms of allergic rhinitis usually do not worsen rapidly and are not life-threatening; it is only a very slow and persistent state. In contrast, the symptoms of hay fever rhinitis are seasonal and usually develop in the spring and fall when pollen is often spread in the air. Once the season is over, the symptoms will be cured without medicine. Based on the above, you may be able to initially determine whether you are suffering from a cold or allergic rhinitis. Of course, in the case that you cannot judge correctly or do not have the right eye medication, it is best to go to the hospital in time to avoid unnecessary trouble.