A sinus infection does not generally cause dizziness.
Dizziness is not a primary symptom of a sinus infection, also known as acute sinusitis. The condition is typically associated with nasal discharge, nasal blockage, swelling, aches, coughing, and a reduced ability to taste and smell.
Patients who have wondered about the connection between a sinus infection and dizziness are generally told by ear, nose, and throat specialists (ENT) that there is no causal connection between the two conditions. One woman who was referred from her General Practitioner to an ENT doctor found that even the second specialist could not isolate why, during her sinus infection bouts, she also experienced dizziness. In the end, the patient was referred to a neurologist and told that it very well could be an inner ear infection.
Other ENT specialists sometimes diagnose that such dizziness is caused by an inflammation of the eighth cranial nerve. Another patient was told that in this case, people with certain sensitivities experience the inflammation as a natural side effect of a common cold. Cranial nerve irritation can last anywhere from a day to several weeks.
Many of the patients who take to the Internet to express their frustration with vague or ineffectual diagnoses of their dizziness also discuss the possibility that it is related to anxiety and panic attack disorders. Once again, much of the evidence here is anecdotal rather than scientific.
While the medical community and literature does not recognize dizziness as a symptom of a sinus infection, there is much patient testimony about the two being wrapped up together within some sort of of larger set of medical issues. Be it the cranial nerve, the middle ear, anxiety, or some other more logical root cause. In the case of a sinus infection, all sorts of other factors--from medication being taken to allergies that layer in on top of the sinusitis-may also come into play with regards to a sufferer experiencing dizziness.