Formaldehyde is a volatile gas that is harmful to the human body, especially to the respiratory organs, and is also classified as a carcinogen by the World Health Organization. After inhaling formaldehyde for a day, firstly, you should immediately get out of this formaldehyde environment and enter into a space with fresh air and ventilation. Secondly, certain treatment measures should be taken according to whether the corresponding symptoms of formaldehyde poisoning have appeared. If there is no feeling, it means that the concentration and amount of formaldehyde inhaled are very low and will not cause damage to the human body, and only a few days of rest is needed. If mild symptoms of poisoning occur, such as sore throat, itchy nose and mild cough, you can take symptomatic medication by inhaling fresh oxygen and using symptomatic medication to relieve sore throat. If serious symptoms occur, such as dizziness, weakness, severe cough, chest tightness, shortness of breath, or even nausea and vomiting, you should seek immediate medical attention and be hospitalized for further treatment.