In brief, if your scalp feels tender, sore, or burning, especially around the hair roots during periods of active shedding, you may have trichidynia. It affects approximately one-third of people with hair loss disorders, is significantly more common in women, and has a documented neurochemical and inflammatory mechanism. It is not imagined. A January 2025 study found substance P tissue levels five times higher in trichodynia patients than in healthy controls, and it is telling you something specific about what is happening in your follicles. Most people who experience scalp pain during hair loss are told one of two things: that it is stress or that it is not a recognized symptom and therefore probably psychosomatic. Trichodynia is a scalp condition characterized by discomfort, pain, or tenderness, often without visible inflammation or lesions. It is not a standalone disease, but often a symptom linked to other medical or psychological conditions. That last sentence is important. Trichodynia is a symptom, not a diagnosis in itself. Where the pain is located, when it appears, and which other symptoms accompany it, all offer diagnostic information about the underlying condition. A 2025 study published in the Journal of Drugs in Dermatology, Dazir et al., Weill Cornell Medical College and University of Pennsylvania, confirmed that scalp pain or tenderness location can offer diagnostic clues about which type of scarring alopecia a patient has, meaning the symptom you might die. Smith's stress is actually clinically informative. What is trichidynia and how common is it? In a study that assessed 249 patients for the presence of trichodinia, 35.7% were found to have been experiencing the syndrome alongside other hair loss conditions. The condition was more common in females than males. Trichodinia, also called burning scalp syndrome or scalp dysthesia, describes pain, burning, stinging, or tenderness at the scalp and hair roots, particularly when touching or combing the hair. It can be continuous or intermittent. It often worsens during periods of active shedding. And despite affecting more than a third of people with hair loss conditions, it is rarely discussed in consultations, rarely documented in medical notes, and rarely treated as a symptom with its own clinical significance. Approximately one-third of patients with trichological disorders experience sensitive scalp symptoms. Telogenafluvium is strongly associated with scalp tenderness, pain, burning sensation, and pruritis, with significantly higher prevalence of sensitive scalp compared to other alopecia types. Alopecia ariata patients also report significantly elevated rates of pruritus and trichodinia, what causes scalp pain at the hair root. The mechanism is now better understood than it was five years ago. Research points to two overlapping processes, neurogenic inflammation and paraphilicular inflammation, both involving the neuropeptide substance P a case control study Public. Heed in the journal of the Egyptian Women's Dermatologic Society in January 2025, Gohari et al. enrolled 35 trichodinia agar patients and 35 healthy controls and measured tissue and serum levels of substance, P. The mean tissue levels of substance P were significantly higher in patients, 448.11 plus 241.24 PG per G, than in controls, 75.78 plus 11.81 PG per G, a nearly six-fold difference, P0. Serum levels were also significantly higher in patients than controls, 325.09 plus 218.43 versus 171.06 plus 42.19 Pgml, P equals sine 0.0002. The study concluded that substance P accompanied by paraphilicular inflammation plays a major role in the pathogenesis of trichodinia. Substance P is a neuropeptide released by sensory nerve endings in the skin. It amplifies pain signals, promotes local inflammation, and contributes to the sensitization of nerve endings so that normally non-painful stimuli, like the weight of your hair or brushing, become uncomfortable. The pain at the hair root is not imagined. It has a measurable neurochemical substrate in elevated substance P and the parapolicular inflammatory environment that this series has covered extensively. 35.7% of hair loss patients experience trichodynia, approximately 1 in 3, significantly more common in women than men. 6X higher tissue substance P levels in trichodynia. Augia patients vs. Healthy Controls. January 2025 Case Control Study, P. 0.00019 of 10. Treatment-resistant trichodinia patients improved after botulinum toxin injections. June 2026 Reader. Telogenofluvium, the strongest association telegenafluvium is strongly associated with scalp tenderness, pain, burning sensation, and pruritus, with significantly higher prevalence of sensitive scalp compared to other alopecia types. During active TE, large numbers of follicles transition simultaneously into telogen, and the physical process of the follicle entering the resting phase combined with the associated parapolicular inflammation appears to generate substance P release at scale. The timing is characteristic, the scalp pain tends to arrive and intensify alongside the shedding wave, then gradually resolves as the acute phase passes. Androgenetic alopecia, the chronic low-grade version. The 2025 substance P study specifically enrolled AGA patients, meaning trichodinia in androgenetic alopecia is a documented phenomenon, not just in acute shedding. In AGA, the parapolicular inflammation that PyLIF research found in 81% of patients is a chronic low-grade process, and it appears to generate a chronic lower intensity scalp sensitivity rather than the acute pain wave of TE. Trichodynia is classified among the allodynea, conditions in which pain is felt on the skin without recognizable external causes or appears to be caused by usually innocuous stimuli. The scalp that hurts when you just touch your hair gently is exhibiting allodynea driven by this sensitization.