Dizziness in the afternoon can be caused by a variety of conditions: 1. If the patient suffers from cervical spondylosis, or strains the body by maintaining the same posture for a long time in the afternoon, cervical spondylosis can compress the nerves, causing insufficient blood supply to the brain and also to the cerebellar brainstem, thus causing dizziness. 2. The patient’s blood pressure is too high causing symptoms of dizziness. 3. The patient suffers from maxillary sinusitis, including acute and chronic maxillary sinusitis. Acute and chronic maxillary sinusitis, both manifest as headache, dizziness and nausea, vomiting, and possible discharge from the nasal cavity on the affected side, with symptoms often heavier in the afternoon. Chronic maxillary sinusitis may also manifest as inability to concentrate, memory loss, the affected side or bilateral nasal cavity may flow purulent discharge, it is recommended to go to the hospital for CT examination of the paranasal sinuses to clarify the diagnosis, and its treatment is mainly anti-inflammatory treatment, commonly used drugs such as metronidazole, ornidazole, cephalosporin antibacterial agents.