One side of face swollen and headache: what to know

Dental infection, skin inflammation, an allergic reaction, or sinus inflammation can swell one side of the face. Allergic rhinitis, a common cold, or chronic sinusitis may cause pressure and congestion, while dehydration, heat exhaustion, or a viral illness can contribute to headache. Dengue fever can cause fever and headache and needs medical advice in the appropriate setting. The combination does not identify one diagnosis by itself; the affected area and associated symptoms matter.

Rest, drink fluids if you can, and note when the swelling and headache began. Use a cool compress for comfort, but do not squeeze a swollen area or apply leftover antibiotics. If tooth pain, nasal discharge, fever, or a recent food, medicine, or insect exposure is present, tell a clinician or pharmacist. Take only medicines suitable for your health history and follow the label. A same-day assessment is sensible when the cause is unclear or symptoms are worsening.

Call emergency services for swelling of the lips, tongue, or throat, breathing difficulty, faintness, new weakness, facial drooping, confusion, speech trouble, or sudden severe headache. Seek urgent review for swelling around the eye, vision change, severe eye pain, high fever, a stiff neck, severe dental pain, or rapidly spreading redness. Do not wait for home treatment if the person appears very unwell or cannot drink.

Ask whether the swelling is more consistent with dental, sinus, skin, or allergic inflammation; whether you need an examination or tests; and which pain relief is appropriate. Mention fever, dental symptoms, discharge, exposures, medicines, travel, and any change in vision or facial movement.