Fortunately, most people with acute sinusitis (sinus infection) do not need to see a doctor in order to recover; only moderate to severe cases necessitate a visit to the doctor, as well as cases characterized by a long duration, including: - Symptoms that last more than a week - Symptoms that worsen after seeming to improve - A persistent fever - A history of recurrent or chronic sinusitis Certain signs and symptoms indicate a serious infection, for which a doctor should be consulted immediately, including: - Pain, swelling or redness around your eyes - High fever - Confusion - Double vision or other vision changes - Stiff neck