Sinus and congestion are common reasons to go to the doctor,
but there are many things you can do first to decrease the drainage and open your airways.
When should you see a doctor in the first two days of respiratory symptoms? (see below ***)
Simple congestion can range from symptoms of irritated throat, hoarseness and night cough from drainage. Tiny airway openings of the sinuses and ears can get stopped up causing pressure pain. Regardless of whether a virus or allergies started the process, you should act to keep from getting worse. It might just be getting around steam, using a neti pot or spraying afrin type nasal spray to keep airways open. OTC pills that help are de-congestants. The usual sudafed (pseudo-ephedrine) is now kept in back with the pharmacist. Out front is the Phenyl-Ephrine like sudafed PE.
Antihistamines can have an extra drying effect. In fact if allergies are the cause, then they get to the source of the problem. A good combo to ask the pharmacist for is a 24 hour claritin-D (loratidine with the Decongestant pseudoephedrine) There are meds to thin the mucous and there are meds to suppress a cough (DextroMethorphan). A good combo that can be added to the above combo is mucinex-dm. The brand name in a 12 hour pill form may be more effective.
If there is a fever and body aches that started abruptly then it might be the flu. There are prescription anti-viral meds that are usually prescribed, especially for high risk persons; meds like tamiflu are most effective if started within 48 hours of starting symptoms. Low risk persons might want to just call their doctor about whether they really need to come in.
If there is a fever with sore throat and tender glands in the neck, it could be strept throat or mono. This might be less likely if you have cough, runny nose or drainage down the throat. Not everyone has white pus pockets in the throat, exposure to someone or even a fever. Streptoccocas bacteria infections need to be treated with anti-bacterial (this means antibiotics). Treatment reduces complications and spread to others.
If you have concerns about the illness. Symptoms like deep moist cough, shortness of breath, feeling lethargic, etc. should not be ignored.