Hi. Thanks for the query. Well, chest congestion, cough and cold is due to viral infection of the respiratory tract. Whereas tooth infection is bacterial in nature. So it can be con-incidental that you have got cold and chest congestion after root canal treatment, however you might be exposed to someone who is already infected causing infection. Do not worry as the viral infection generally resolves once the virus completes its cycle in human body. As of now you can start with supportive treatment to relieve the symptoms like: -Take a combination of decongestant like Phenylephrine, Mucolytic like Ambroxol and anti allergic Levocetrizine and another combination of Acetaminophen and Ibuprofen -Take cough expectorant containing Gueifenesin and cough suppressant containing Dextromethorphan. -Chew a Vitamin C pellet daily. -Do steam inhalations. -Avoid spicy and chilled foods. -Sip on warm water throughout the day -Do warm compresses over chest. Hopefully the symptoms will resolve within a week and if it worsen consult a General Physician and get evaluated. Hope this helps. Regards Dr. Honey Arora, Dentist