Scalp Allodynia During Viral Illness: Cytokine Storms, Systemic Inflammation, and Nerve Pain

Many people describe an unusual symptom during COVID-19 or another viral illness: “my hair hurts.” Hair itself cannot feel pain because it is made of dead keratin. Usually, the discomfort comes from the scalp, the skin around the hair follicles, or the nerves supplying the scalp.

This symptom may feel like tenderness, burning, prickling, pressure, or pain when the hair moves, when the scalp touches a pillow, or when someone brushes their hair. The medical term for pain caused by a normally harmless touch is allodynia. Scalp allodynia can occur with viral infections, fever, headaches, migraine, and inflammation affecting the body’s pain-processing system.

Why does hair hurt during COVID?

The question “hair hurts during COVID” is often related to increased sensitivity in the scalp rather than a problem with the hair shaft. Several processes may contribute:

• Inflammatory chemicals: During an infection, the immune system releases signaling proteins called cytokines. These help coordinate the immune response, but they can also make pain-sensing nerves more sensitive.
• Fever and illness stress: Fever, poor sleep, dehydration, and muscle tension can worsen headaches and scalp tenderness.
• Migraine or viral headache: COVID-19 and other infections may trigger headaches. Migraine can cause allodynia, meaning even light touch or hair movement feels painful.
• Irritated sensory nerves: The scalp is supplied by branches of the trigeminal and upper cervical nerves. Inflammation or abnormal nerve signaling can make these nerves overreact to ordinary touch.
• Skin irritation: Sweating, frequent washing, dry skin, hats, masks, or new hair products can irritate the scalp during an illness.

Scalp pain is not specific to COVID-19. Influenza, other respiratory viruses, sinus infections, shingles, and noninfectious headaches can cause similar symptoms. A symptom alone cannot confirm which infection is present.

Is scalp pain a sign of a cytokine storm?

The phrase “cytokine storm” is often used online to explain severe symptoms during COVID-19. In medicine, it refers to an excessive, poorly controlled immune response that can cause widespread inflammation and organ dysfunction. It is associated with serious illness, not simply with having a headache or tender scalp.

A painful or sensitive scalp by itself does not show that a cytokine storm is occurring. Most people with viral infections have a temporary immune response that settles as they recover. Cytokine activity is complex, and a person’s symptoms cannot reliably indicate their cytokine levels.

Severe systemic inflammation may involve problems such as low oxygen levels, confusion, persistent chest pain, severe weakness, or difficulty breathing. These symptoms require urgent medical attention. Scalp allodynia without other serious warning signs is more commonly linked to headache, nerve sensitivity, fever, or local skin irritation.

What does scalp allodynia feel like?

People may describe:

• Pain when brushing, washing, or touching the hair
• A burning, tingling, or sunburn-like sensation
• Tenderness when resting the head on a pillow
• Pain when moving the hair or tying it back
• A tight, bruised, or pressure-like feeling
• Increased sensitivity on one side of the scalp or across the whole scalp

The discomfort may begin during the infection or shortly afterward. It often improves as the fever, headache, and general inflammation improve. If it continues for several weeks, keeps worsening, or interferes with sleep and daily activities, arrange a medical assessment.

Other possible causes

COVID-19 is only one possible explanation. A clinician may also consider:

• Migraine, including migraine without a severe headache
• Tension-type headache or neck muscle strain
• Influenza or another viral infection
• Shingles, especially if pain is confined to one side
• A scalp infection or inflammation
• Contact dermatitis from shampoo, dye, dry shampoo, or other products
• Occipital neuralgia, involving irritated nerves at the back of the head
• Medication side effects or withdrawal from caffeine
• Less commonly, conditions affecting blood vessels, nerves, or the immune system

Shingles deserves particular attention. Pain, burning, or tingling may occur several days before a rash appears. A one-sided blistering rash on the scalp, forehead, or around the eye should be assessed promptly because early treatment can reduce complications.

Scalp pain should also be distinguished from hair shedding. Temporary increased shedding can occur two to four months after a significant infection or fever. This is often called telogen effluvium and is different from scalp allodynia. It is usually temporary, although a healthcare professional should evaluate sudden, patchy, or persistent hair loss.

What can you do at home?

If your symptoms are mild and you otherwise feel stable, supportive care may help:

• Rest and drink enough fluid to keep your urine pale yellow, unless a doctor has given you fluid restrictions.
• Keep hair loose and avoid tight ponytails, braids, clips, or heavy extensions.
• Use lukewarm water and a gentle, fragrance-free shampoo.
• Avoid scratching, vigorous scalp massage, hair dye, and new products until the skin feels normal.
• Reduce bright light and noise if the pain resembles a migraine.
• Use a cool or warm compress, depending on which feels more comfortable.
• Consider acetaminophen/paracetamol or another appropriate pain reliever only if it is safe for you. Follow the package directions and avoid doubling up on products that contain the same ingredient.
• If you have COVID-19 symptoms, follow current local testing, treatment, and infection-control guidance. People at higher risk of severe COVID-19 may benefit from early antiviral treatment, which must be discussed promptly with a clinician.

Do not apply steroid creams, essential oils, numbing products, or prescription medicines to the scalp without medical advice. These treatments may irritate the skin or mask symptoms that need evaluation.

If you are unsure what your symptoms may mean, you might consider a free, online symptom check, using the doctor approved Ubie Symptom Checker. It cannot diagnose a condition or replace a clinician, but it can help you organize symptoms and decide what level of care may be appropriate.

When should you speak to a doctor?

Speak to a doctor if scalp pain is moderate, severe, recurrent, or not improving as the viral illness gets better. You should also arrange medical advice if you have:

• A new rash, blisters, sores, swelling, pus, or marked redness
• Pain mainly on one side of the scalp or face
• Eye pain, a rash near the eye, or vision changes
• Persistent fever or symptoms that improve and then become worse
• Severe headache that is new or unusual for you
• Neck stiffness, repeated vomiting, weakness, numbness, or balance problems
• Ongoing symptoms after recovering from COVID-19
• A weakened immune system, pregnancy, or a condition that increases the risk of severe infection

Seek emergency care immediately for difficulty breathing, blue or gray lips, severe chest pain or pressure, new confusion, fainting, inability to stay awake, sudden weakness on one side, trouble speaking, or a sudden “worst-ever” headache. These symptoms can signal a serious problem and should not be attributed to ordinary scalp sensitivity.

In most cases, tender or painful scalp during a viral illness reflects temporary nerve sensitivity, headache, fever, or skin irritation—not a cytokine storm. Still, symptoms that are severe, persistent, or accompanied by neurological or breathing problems should be assessed by a healthcare professional.