Headache and nausea symptoms often occur simultaneously and can be attributed to various underlying causes. One common trigger is migraines, which frequently manifest with throbbing head pain and an upset stomach. Tension headaches can also induce headache and nausea symptoms due to muscle tension and stress. Additionally, sinusitis, a sinus infection or congestion, can lead to head pressure and nausea. Dehydration and certain medications may exacerbate these symptoms. Identifying the specific cause is essential for effective treatment. Consult a healthcare professional to determine the underlying issue and develop a suitable plan for relieving headache and nausea symptoms.