Medical Oncologist
Neurological emergency
Sudden Confusion, Seizure or — Weakness on One Side
A new seizure, sudden confusion or sudden weakness down one side of the body in a cancer patient needs emergency care now — not a call to clinic tomorrow. These are warning signs the brain needs immediate assessment.
Medically reviewed by Dr. Bharati Devi Gorantla, Medical Oncologist, MBBS · MD · DM (Adyar, Chennai) · ECMO · MRCP SCE (UK) · Last reviewed August 2026
- Call 108 or go now — A first-ever seizure in a cancer patient is always an emergency, regardless of how quickly it passes.
- Do not wait for clinic — These symptoms cannot be assessed safely over the phone. Go to the emergency department.
- Note the time — Treatment decisions depend on when the symptom started. Write down the exact time you first noticed it.
- Bring the medication list — The emergency team needs to know every drug, supplement and herbal remedy the patient is taking.
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A new seizure, sudden confusion or sudden one-sided weakness in a cancer patient is a medical emergency. Call 108 or go directly to the nearest emergency department now. Do not wait for your oncology team to call back. Bring the full medication list and note the exact time the symptom started.
If a symptom below applies to you, do not wait for a callback. Call 1800-202-8726 or go to your nearest emergency department.
While you are on the way to emergency
- Call 108 or have someone drive — do not drive yourself if the patient had a seizure.
- Write down the exact time the symptom first started.
- Do not give food, water or medication unless the patient is fully awake and swallowing normally.
- Bring every medication — prescription drugs, supplements and herbal remedies.
- Bring the oncology team contact number and the last clinic letter if you can find it quickly.
- If a seizure happened: note how long it lasted, which body parts were affected, and whether consciousness was lost.
- Stay with the patient at all times.
Meet the Specialists
17+ senior cancer specialists. One panel for your case.
Trained at AIIMS, Tata Memorial, and leading international centres. Combined 150+ years of experience. Every complex case is reviewed by 3+ of them — together.
Medical Oncologist
Dr. C. Raghavendra Reddy
MBBS(Gold Medal), DNB(General Medicine), DM(Medical Oncology)(Gold Medal)
Medical Oncologist
Dr. Bharati Devi Gorantla
MBBS, MD(General Medicine), DM(Medical Oncology)(Adyar,Chennai), ECMO, MRCP SCE(UK)
Medical Oncologist
Dr. Owais Mohammed
MBBS, MD (General Medicine), DrNB (Medical Oncology), ECMO, MRCP SCE (Medical Oncology) (UK)
Medical Oncologist
Medical Oncologist
Surgical Oncologist
Dr. Muralidhar Muddusetty
MBBS (AIIMS), MS (Surgery) (AIIMS), DNB (Surgical Oncology), MRCS (Edinburgh)
Surgical Oncologist
Surgical Oncologist
Surgical Oncologist
Dr. Vinay Mamidala
MBBS, MS(General Surgery), M.Ch(Surgical Oncology), FMAS, FARIS(Ongoing)
Surgical Oncologist
Radiation Oncologist
Radiation Oncologist
Radiation Oncologist
Hematologist
Interventional Radiologist
Dr. Mohammed Imran
Surgical Oncologist
Dr. Vajja Sandeep Kumar
MBBS, MS (General Surgery), DrNB (Surgical Oncology), FALS Oncology
Surgical Oncologist
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Not sure whether this counts as an emergency?
Call the helpline. It is always better to check than to wait.
Why does cancer cause sudden seizures or confusion?
Cancer can affect the brain in several ways. Tumour cells can spread to the brain from another part of the body — this is called brain metastasis. A tumour or the swelling around it can press on brain tissue and trigger a seizure, sudden confusion or one-sided weakness.
Some blood chemistry changes — such as very low sodium — can cause neurological symptoms that look identical to a brain event. Some cancer treatments can also affect the brain. The emergency team will check for all of these causes.
A CT or MRI scan of the brain is usually the first step and can be arranged quickly in an emergency setting. The earlier the cause is found, the more options there are.
How do you tell this apart from ordinary tiredness or a familiar headache?
| Symptom | Likely not an emergency | Go to emergency now |
|---|---|---|
| Headache | Mild, gradual, similar to usual headaches, relieved by rest | Sudden and severe, worst ever, came on in seconds, or with vomiting or confusion |
| Confusion | Drowsy, forgetful, tired — but knows where they are and recognises family | Cannot recognise family, disoriented, getting worse rather than better |
| Weakness | General fatigue, both sides equally, improves with rest | One side only — face, arm or leg — sudden onset, does not improve |
| Speech | Slow or quiet due to fatigue, makes sense when they try | Slurred, finding wrong words, or cannot speak or understand — sudden change |
| Typically starts | Gradual worsening over hours to days | Sudden onset — seconds to minutes — is the key warning sign for all of the above |
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Common questions
Frequently asked questions
The seizure lasted only a minute and they seem fine now. Do we still need to go to hospital?
Yes. A first seizure in a cancer patient always needs emergency assessment, even if it was brief and the person seems recovered. A period of normal-seeming behaviour after a seizure is well recognised and does not mean it is safe to wait. The underlying cause has not been identified or treated. The emergency team needs to scan the brain and check blood results before you go home.
They already have brain metastases. Does a new seizure still need emergency care?
Yes. A new or different seizure — or one that lasts longer than usual — in someone with known brain metastases needs the same emergency assessment as a first seizure. It may mean the metastases have changed, that swelling has increased, or that anti-seizure medication needs to be adjusted. Only a scan and blood tests can establish which, and those cannot be done over the phone.
What will happen when we arrive at the emergency department?
Tell the triage nurse immediately that the patient has cancer and has had a seizure or sudden neurological symptom. They will check blood pressure, oxygen levels and blood glucose, and take blood tests to look for metabolic causes. A CT or MRI scan of the brain is usually arranged quickly. Your oncology team will be contacted to share the treatment history. Bring every medication the patient takes — that list changes the investigation.
Could the medication be causing this?
Some medications used in cancer treatment, and some used to manage side effects, can affect the brain or alter blood chemistry in ways that cause neurological symptoms. This is one of the main reasons the emergency team needs the full medication list. Do not stop any medication without being told to, and do not give extra doses of anything while waiting to be seen. The team will review everything once they have the blood results.