What should you know about stomach and headache?

Nausea, loose stools, vomiting, or reduced appetite may accompany a stomach infection. Thirst, dry mouth, darker urine, or light-headedness can point towards dehydration, especially after vomiting, diarrhoea, exercise, or time in hot weather. Congestion and facial pressure may occur with a cold, allergic rhinitis, or chronic sinusitis, while body aches or fever can occur with COVID-19 or dengue fever. Anxiety can also affect digestion and trigger head pain. These patterns are clues, not a diagnosis; the direction is not reversed, so having a headache does not by itself identify a stomach condition.

Rest somewhere cool and quiet. Take frequent small sips of water or an oral rehydration drink if you have lost fluid. If you can eat, choose light foods and avoid alcohol, very rich meals, and anything that clearly worsens nausea. Record when the symptoms began, your temperature if available, bowel changes, vomiting, recent heat exposure, new foods, medicines, and travel. Do not take repeated pain medicine on an empty stomach; follow the label and ask a pharmacist if vomiting, dehydration, pregnancy, or other health conditions affect your options.

Seek urgent help for a sudden severe headache, confusion, fainting, a stiff neck, weakness, trouble speaking, severe or worsening abdominal pain, blood in vomit or stool, or inability to keep fluids down. Get prompt medical advice for fever with a severe headache, a new rash, persistent vomiting, or symptoms after substantial heat exposure. Arrange a clinical review if the pattern keeps returning, lasts beyond a short illness, or is interfering with eating and drinking.

Ask whether your symptoms fit dehydration, an infection, sinus symptoms, heat exhaustion, or another cause; which examination or tests are appropriate; which fluids and foods are suitable; and which pain medicines are safe with your medical history.