In clinical practice, it is common for patients experiencing frequent headaches to be referred for further investigations, such as blood tests or diagnostic imaging, such as a CT scan or MRI.
While most headaches are primary headaches and not life-threatening, some individuals experience associated signs that act as warning symptoms of a more significant underlying disease. In the medical world, these are referred to as headache red flags.
Recognising these red flags is essential, as they may indicate a secondary headache, where the pain is a symptom of a more dangerous condition, rather than primary headaches like migraines or tension headaches.
Primary vs Secondary Headaches
To understand when to seek medical attention, we must first distinguish between the two main types of head pain:
Primary headaches
These are neurological conditions that occur without an underlying structural cause or infection. They are often triggered by stress, lack of sleep, or alcohol, and include:
- Migraines (often felt on one side of the head)
- Cluster headaches
- Tension headaches
Secondary headaches
These occur due to a secondary health issue affecting the brain, blood vessels, or systemic health. This could range from a sinus infection or pregnancy-related complications to more severe issues like a stroke, brain tumour, or cancer. While typically headache pain is not a cause for alarm, a new headache with red flags should never be ignored.
General Headache Red Flags
The following red flags of headache are essential to monitor, especially if they represent a change from your previous headaches:
- Sudden onset headache: Pain that peaks in intensity almost always, quite suddenly
- New headache in adults: Particularly those over the age of 50
- Systemic signs: Headache symptoms accompanied by fever, swelling, vomiting, or unexplained weight loss
- Head injury: Pain that begins or worsens after a trauma
- Valsalva manoeuvre triggers: Headache pain triggered by coughing, sneezing, or straining
- Progressive worsening: When the headache gets worse every day regardless of rest or medication
In-Depth Explanation of Headaches Requiring Medical Attention
This section outlines common clinical scenarios where red flags for headaches may be present.
Thunderclap Headache
A thunderclap headache is a sudden-onset headache that often feels like a “clap of thunder,” reaching maximum severity within seconds. This may be an indicator of bleeding in the brain (subarachnoid hemorrhage) or a ruptured aneurysm. This is considered a serious red flag that requires urgent clinical assessment.
Neurological Symptoms
If your headache is accompanied by neurological symptoms, it may be a sign of stroke or other serious neurological conditions. Look out for:
- Weakness or numbness in the face or limbs
- Double vision or other visual disturbances
- Loss of vision
- Confusion or trouble speaking
Fever and Neck Stiffness
A severe headache combined with fever and neck stiffness (nuchal rigidity) is a classic red flag for a serious infection of the central nervous system, such as meningitis. When the membranes protecting the brain and spinal cord become inflamed, it creates intense pain that typically worsens with movement.
A key clinical test is the inability to touch your chin to your chest due to extreme pain or involuntary muscle resistance. If these systemic signs are accompanied by a rash, vomiting, or an altered mental state, it is essential to seek immediate medical attention, as these conditions can be life-threatening if left untreated.
New Headache in Older Adults
While primary headaches like migraines usually develop earlier in life, a new headache appearing for the first time in adults over the age of 50 is a significant red flag. In these cases, clinicians must rule out secondary headaches caused by a brain mass (tumour) or giant cell arteritis (temporal arteritis).
Giant cell arteritis involves inflammation of the lining of the arteries, particularly those in the head and temples. If left untreated, it can potentially lead to vision loss or stroke. If you are over 50 and notice new pain in the temples, scalp tenderness, or jaw discomfort while eating, a complete medical evaluation is required.
Head Injury and Post-Traumatic Headache
Any headache that develops or worsens following a head injury or physical trauma must be carefully monitored. While a mild headache is common after a concussion, certain symptoms indicate bleeding inside the skull or increased intracranial pressure.
You should seek medical attention immediately if you experience:
- Worse or increasing pain intensity
- Repeated episodes of vomiting
- Confusion, drowsiness, or difficulty staying awake
- Memory disturbance or numbness in the body
These red flags may indicate an intracranial haematoma (internal bleeding) that requires urgent medical assessment, which may include a CT scan and further management to prevent complications.
Headache Triggered by Coughing, Sneezing, or Straining
A headache that is specifically triggered by a Valsalva manoeuvre, such as coughing, sneezing, or physical straining, may suggest an underlying pressure-related cause. These are often referred to as “exertional” or “cough headaches.”
While they can sometimes be benign, they are frequently associated with increased intracranial pressure or structural abnormalities, such as Chiari malformations, which can affect cerebrospinal fluid dynamics around the brain. Because these headaches are triggered by activities that momentarily increase the pressure inside the head, they generally require a full neurological assessment to ensure there is no underlying mass or structural issue.
More and Less Concerning Red Flags Headache Features
Headache red flags are important to identify, with some headache patterns being generally less concerning when they remain stable over time. A headache is typically viewed as a primary headache if the symptoms:
- Have remained unchanged for more than three months
- Alternate between the left and right sides of the head
- Are consistent with a previous headache diagnosis, like migraines
However, any sudden change in pattern, spike in intensity, or development of neurological symptoms should prompt a complete clinical review to exclude secondary headaches.
Pre-Existing Conditions and Headache Risk Factors
Certain medical histories can increase the likelihood that a new headache is secondary in nature rather than a primary headache disorder. Identifying these factors is often a vital part of clinical practice to ensure no underlying disease is missed.
Potential high-risk factors can include:
- Vascular Disease: A history of stroke, bleeding in the brain, or an aneurysm
- Cancer Diagnosis: Both previous and current cancer diagnoses require new headache symptoms to be screened for potential mass or metastasis
- Neurological Conditions: Pre-existing epilepsy or multiple sclerosis
- Immune Health: Autoimmune or inflammatory disorders that affect the body and immune function
- Connective Tissue Disorders: Conditions that may affect the structural integrity of the brain or blood vessels
In these cases, any deviation from previous headaches is treated with a high level of caution. At Sydney Headache & Migraine Clinic™, we take these factors into account during your initial consultation to ensure your treatment plan is both safe and effective.
How Sydney Headache & Migraine Clinics Can Help
At Sydney Headache & Migraine Clinic™, we provide a structured assessment to determine whether your symptoms are consistent with primary headaches or whether red flags suggest a secondary headache requiring further medical investigation.
Once serious underlying causes have been clinically excluded, our clinicians utilise the Watson Headache® Approach, a medication-free and surgery-free method. This approach focuses on identifying potential underlying drivers of pain, particularly the role of cervical spine dysfunction and sensitisation of the trigeminocervical complex. For those experiencing frequent or progressively worsening headache patterns, a complete clinical assessment is an essential step in guiding appropriate management.
Book your initial consultation today and take the first step toward understanding your head pain.
References
Do, T.P. et al. (2019) Red and orange flags for secondary headaches in clinical practice. Neurology, 92(3), pp. 134–144. doi:10.1212/wnl.0000000000006697.
M, S. et al. (2003) Red flags in patients presenting with headache: Clinical indications for neuroimaging. The British Journal of Radiology, 76(908), pp. 532–535. doi:10.1259/bjr/89012738.
Rosenblum, J. S., Pomeraniec, I. J., & Heiss, J. D. (2022). Chiari malformation (update on diagnosis and treatment). Neurologic Clinics, 40(2), 297–307. https://doi.org/10.1016/j.ncl.2021.11.007
Wijeratne, T. et al. (2023a) Secondary headaches – red and green flags and their significance for diagnostics. eNeurologicalSci, 32, p. 100473. doi:10.1016/j.ensci.2023.100473.
