How long does whole brain radiotherapy take to work for brain metastases?

Whole brain radiotherapy delivers radiation to the brain across a planned course. Its effect on metastatic tumour cells is not judged from the treatment-room visit alone. Headache, weakness, balance problems, seizures or confusion may improve at different speeds, and swelling around a metastasis can temporarily make symptoms worse or require steroid treatment.

Your oncology team assesses neurological symptoms, medicine needs and follow-up scans together. Imaging changes can take time to interpret, and symptoms may also be influenced by the original cancer, swelling or other treatments. The aim may include controlling existing brain disease and reducing the chance of further growth, depending on your plan.

Take steroids, anti-seizure medicines and other prescribed treatments exactly as instructed; do not stop a steroid suddenly unless your team tells you to. Ask about driving, work, exercise and support at home if balance, memory or alertness is affected. Keep a brief record of headaches, vision, strength, speech, walking and seizure symptoms for review.

Fatigue, scalp sensitivity, hair loss or nausea can occur during or after treatment. Rest, drink according to your clinical advice and protect irritated skin from friction or harsh products. Attend planned reviews so the team can adjust symptom medicines and decide when imaging is useful.

Seek emergency help for a new seizure, loss of consciousness, sudden weakness or numbness, new trouble speaking, severe or rapidly worsening headache, repeated vomiting, marked confusion or a sudden change in vision. Contact your radiotherapy team promptly for persistent vomiting, worsening symptoms or difficulty taking prescribed medicines.

Ask: What symptom improvement should we watch for? Could swelling temporarily worsen my symptoms? How should I use steroids or anti-seizure medicine? When will neurological review and imaging occur? Which changes require emergency help?