What is Allodynia?

Some people with migraine may say things like, “Even my hair hurts today!” and they are not exaggerating! Many people with migraine disease experience allodynia, or pain from a stimulus that does not normally provoke pain.¹ Allodynia is not only a painful migraine symptom, but sometimes it can be a tell-tale sign about the progression of migraine disease and potential treatment needs.

What does it mean to have allodynia when you have migraine disease? And what can you do about it?

Allodynia and Migraine

An estimated 40% to 70% of people with migraine experience allodynia when they have migraine attacks.² Allodynia can present in several ways:

• Tactile allodynia (also called cutaneous or static allodynia) is pain from a stimulus that touches your skin. An example is feeling pain when you lightly touch your legs, face, or head.
• Mechanical allodynia (also called dynamic allodynia) is pain from a stimulus moving across your skin. You might feel pain when a sweater moves across your skin or when you brush your hair.
• Thermal allodynia is pain from minor temperature changes. You might feel pain while washing your hands in warm water that usually wouldn’t bother you.

Experts believe that people with migraine are susceptible to allodynia because of a process called central sensitization, a state in which the central regions of the brain get overexcited and hyper-responsive to stimuli but don’t “downshift” as they should when everything’s working properly.³ Migraine attacks can shift the brain into that overdrive mode, making ordinary sensations painful.  

What Allodynia Tells Us About Migraine

Experts have observed strong correlations between allodynia and migraine burden:

• People who have chronic migraine (15 or more headache days per month with at least 8 days per month with migraine features for at least three months) are more likely to experience allodynia than people who have a few attacks each month.^4,5 
• People with migraine and allodynia tend to use more acute treatments and have less successful responses to acute treatments than people without allodynia.^4,5
• Cutaneous allodynia is also considered a strong predictor of the risk of disease escalation or chronification. People with migraine who have severe allodynia symptoms are at greater risk for a significant increase in the frequency and severity of attacks than those who don’t have allodynia.^4,6
• People with migraine and allodynia are more likely to also have depression and/or anxiety.^5,6 

People who have comorbid pain conditions such as irritable bowel syndrome, chronic fatigue syndrome, or fibromyalgia are more likely to have allodynia.⁶

What Allodynia Might Be Telling You About Your Migraine Treatment

If you typically get allodynia with your migraine attacks, it’s important to treat early before the allodynia develops.⁷ This can be tricky because some people’s migraine attacks start with such vague symptoms that they can’t always tell if it’s a tension-type headache or a migraine attack.

Using an acute treatment during the prodrome phase (or when the non-headache symptoms first appear) can help shorten the attack and prevent an attack from recurring 12-24 hours after treatment. Some telltale migraine prodrome symptoms include yawning, neck stiffness, sensitivity to light or sound, frequent urination, increased thirst, or mood changes.

Second, if you’re using acute medications for attacks more often than you used to, and you notice that you’ve developed new or worsening allodynia symptoms, this may be a sign that you’re at higher risk for another type of headache disorder called medication adaptation headache (MAH), formerly known as medication overuse headache (MOH) or rebound headache. Using certain acute medications too frequently may make attacks come back sooner and become harder to treat. The International Headache Society guidelines say that using medications containing triptans, caffeine, butalbital, or opioids 10 or more times per month for at least three months, or acetaminophen or NSAIDS like ibuprofen or naproxen 15 or more times per month for at least three months regularly increases your risk for developing MAH.⁸ Although these are the current guidelines, people may have different thresholds for developing MAH.⁹

Acute treatment options that are not known to cause medication adaptation headache include:

• Neuromodulation devices like Nerivio, Cefaly, Relivion, Neurolief or SAVI Dual
• Gepants such as ubrogepant, rimegepant or zavegepant
• Anti-nausea medications like metoclopramide or prochlorperazine
• Nerve blocks

Third, experiencing allodynia both during AND between migraine attacks may indicate that your migraine disease is progressing to chronic migraine or that your current treatments are not providing adequate relief. This should be discussed with your provider to potentially begin preventive treatment or reevaluate your current migraine treatment plan.

Allodynia, A Useful Indicator?

A 2023 multi-center study involving more than 700 individuals with high-frequency episodic migraine (HFEM) or chronic migraine (CM) found that some patients may benefit from longer trials of CGRP monoclonal antibody (CGRP mAb) treatments to see improvement in symptoms like allodynia.¹⁰

In both clinical practice and research settings, preventive migraine medications are typically evaluated over a 12-week trial period. If a patient doesn’t respond during that time, the treatment is often discontinued. However, findings from this study challenge that approach—showing that many individuals who did not respond to CGRP monoclonal antibodies at 12 weeks experienced meaningful improvements by 24 weeks.¹⁰The researchers encouraged healthcare providers to consider extending the trial period for CGRP mAbs and to monitor for symptom improvements—such as a reduction in allodynia and light sensitivity, as possible early signs of central desensitization and treatment effectiveness.¹⁰

Key Takeaways

Although allodynia can be an uncomfortable and often overlooked symptom, it can also serve as an important clinical clue in guiding migraine treatment. Using acute medications early in the attack, trialing treatment options that are not known to cause medication adaptation headache, such as neuromodulation, gepants, or nerve blocks, and starting preventive therapies can all play a role in improving outcomes. It’s also worth noting that some treatments, like CGRP monoclonal antibodies, may require a longer trial period before their full benefits are seen. Be sure to discuss all of your symptoms—including allodynia—with your healthcare provider.

References

1. https://www.ncbi.nlm.nih.gov/books/NBK537129/ He Y, Kim PY. Allodynia. [Updated 2023 Sep 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537129/ 
2. https://americanheadachesociety.org/research/library/what-allodynia-tells-us-about-migraine-q-a-with-david-dodick-md-fahs
3. https://thejournalofheadacheandpain.biomedcentral.com/articles/10.1186/s10194-023-01651-9#Sec8 Pijpers, J.A., Kies, D.A., van Zwet, E.W. et al. Cutaneous allodynia as predictor for treatment response in chronic migraine: a cohort study. J Headache Pain 24, 118 (2023). 
4. https://pmc.ncbi.nlm.nih.gov/articles/PMC10632231/ Lipton RB, Buse DC, Nahas SJ, Tietjen GE, Martin VT, Löf E, Brevig T, Cady R, Diener HC. Risk factors for migraine disease progression: a narrative review for a patient-centered approach. J Neurol. 2023 Dec;270(12):5692-5710. doi: 10.1007/s00415-023-11880-2 
5. https://americanheadachesociety.org/research/library/what-allodynia-tells-us-about-migraine-q-a-with-david-dodick-md-fahs
6. https://pubmed.ncbi.nlm.nih.gov/19788473/ Tietjen GE, Brandes JL, Peterlin BL, Eloff A, Dafer RM, Stein MR, Drexler E, Martin VT, Hutchinson S, Aurora SK, Recober A, Herial NA, Utley C, White L, Khuder SA. Allodynia in migraine: association with comorbid pain conditions. Headache. 2009 Oct;49(9):1333-44. doi: 10.1111/j.1526-4610.2009.01521.x. PMID: 19788473.
7. https://americanheadachesociety.org/research/library/allodynia-migraine-treatment-q-a-with-dr-richard-lipton
8. https://ichd-3.org/8-headache-attributed-to-a-substance-or-its-withdrawal/8-2-medication-overuse-headache-moh/
9. Lipton, R.B., Serrano, D., Nicholson, R.A., Buse, D.C., Runken, M.C. and Reed, M.L. (2013), Impact of NSAID and Triptan Use on Developing Chronic Migraine: Results From the American Migraine Prevalence and Prevention (AMPP) Study. Headache: The Journal of Head and Face Pain, 53: 1548-1563. https://doi.org/10.1111/head.12201
10. https://pmc.ncbi.nlm.nih.gov/articles/PMC10513886/ Barbanti P, Aurilia C, Egeo G, Torelli P, Proietti S, Cevoli S, Bonassi S; Italian Migraine Registry study group. Late Response to Anti-CGRP Monoclonal Antibodies in Migraine: A Multicenter Prospective Observational Study. Neurology. 2023 Sep 12;101(11):482-488. doi: 10.1212/WNL.0000000000207292.