6.6 Dandruff, Alopecia and Hair Shaft Disorders
Key Takeaways
- Dandruff is medically termed pityriasis and is associated with the naturally occurring scalp fungus Malassezia feeding on sebum fatty acids.
- Pityriasis capitis simplex is dry, flaky scaling; pityriasis steatoides is the greasy, waxy, inflamed form requiring medical referral.
- Androgenetic alopecia is the most common hair loss pattern and is hormonally and genetically driven.
- Alopecia areata presents as sudden, smooth, round patches of complete hair loss and requires medical referral.
- Traction alopecia is caused by sustained tension from tight braids, weaves and extensions and becomes permanent if the tension continues.
Dandruff, Alopecia and Hair Shaft Disorders
Exam Focus: This section separates the conditions a cosmetologist may service with modification from those requiring referral. Learn the two pityriasis classifications, the distinguishing feature of alopecia areata, the reversibility window for traction alopecia, and the shaft disorders — trichoptilosis, trichorrhexis nodosa, monilethrix and canities — by their descriptions.
1. Scalp Disorders: Dandruff (Pityriasis)
Pityriasis is the technical medical term for dandruff, characterized by excessive production and shedding of epidermal skin cells from the scalp.
The Microorganism Factor: Malassezia
Medical research confirms that dandruff is caused by an overgrowth of a naturally occurring, lipophilic (oil-eating) micro-fungus called Malassezia (formerly Pityrosporum ovale). When sebum production surges, Malassezia feeds on the fatty acids, irritating the scalp and causing epidermal skin turnover to accelerate drastically.
Classifications of Pityriasis
| Classification | Clinical Presentation & Symptoms | Salon Treatment vs. Referral Protocol |
|---|---|---|
| Pityriasis Capitis Simplex (Classic Dry Dandruff) | • Scalp irritation, pruritus (itching).<br/>• Large, white/translucent dry flakes that shed freely onto shoulders and clothing. | Safe to service in salon. Treat with professional anti-dandruff shampoos containing zinc pyrithione, selenium sulfide, ketoconazole, or coal tar, followed by scalp massage and moisturizing treatments. |
| Pityriasis Steatoides (Greasy / Waxy Dandruff) | • Accumulation of greasy, yellowish, waxy scales mixed with excess sebum.<br/>• Scales adhere tightly to the scalp in crusts.<br/>• Often accompanied by redness and inflammation (seborrheic dermatitis). | If mild, treated with anti-dandruff regimens. If the scalp is severely inflamed, weeping, bleeding, or infected, service is CONTRAINDICATED; refer client directly to a physician. |
2. Hair Loss Disorders: The Alopecias
Alopecia is the technical medical term for abnormal hair loss, thinning, or baldness. Normal daily shedding ranges between 50 and 100 hairs; shedding exceeding this rate or developing in distinct patterns indicates an underlying disorder.
┌──────────────────────────────────────────────────┐
│ CLASSIFICATIONS OF ALOPECIA │
└──────────────────────────────────────────────────┘
│
┌───────────────────┬────────────────────┼───────────────────┬───────────────────┐
▼ ▼ ▼ ▼ ▼
┌───────────────┐ ┌───────────────┐ ┌────────────────┐ ┌───────────────────┐ ┌───────────────┐
│ ANDROGENETIC │ │ALOPECIA AREATA│ │TOTALIS/UNIVERS.│ │POSTPARTUM ALOPECIA│ │ TRACTION │
│ (DHT-Driven) │ │ (Autoimmune) │ │ (Total Loss) │ │(Hormone Shift) │ │(Tight Pulling)│
└───────────────┘ └───────────────┘ └────────────────┘ └───────────────────┘ └───────────────┘
Detailed Alopecia Classifications
| Disorder | Pathophysiology & Clinical Presentation | Client Prognosis & Approved Treatments |
|---|---|---|
| Androgenetic Alopecia | Hereditary progressive miniaturization of terminal hair into fine vellus hair. Triggered by genetic sensitivity to dihydrotestosterone (DHT), a derivative of testosterone. In men, presents as receding hairline and crown thinning (male pattern baldness); in women, presents as generalized thinning over the crown with preserved front hairline. | FDA-approved treatments include topical Minoxidil (over-the-counter for men and women) and oral Finasteride (prescription oral medication for men only; contraindicated in women of childbearing potential). |
| Alopecia Areata | An autoimmune disorder in which the body's immune system mistakenly attacks its own hair follicles at the bulb. Characterized by the sudden appearance of round or oval, smooth bald patches on the scalp. Hairs at patch margins show characteristic "exclamation point" narrowing at the root. | Can occur at any age. Patches frequently regrow spontaneously within a year, or may recur. Medical treatments include corticosteroid injections. |
| Alopecia Totalis | Progression of alopecia areata leading to the complete loss of all scalp hair. | Requires dermatologist care; cosmetic wigs and prosthetics recommended. |
| Alopecia Universalis | Complete loss of all body hair, including scalp, eyebrows, eyelashes, axillary, and pubic hair. | Systemic autoimmune manifestation. |
| Postpartum Alopecia | Temporary hair loss experienced by mothers following childbirth. During pregnancy, elevated estrogen levels prolong the anagen growth phase; following delivery, sudden hormone drops plunge massive follicle groups into the telogen resting phase simultaneously. | Reassure client that normal growth cycles typically self-correct within 9 to 12 months postpartum without medical intervention. |
| Telogen Effluvium | Premature shedding of large numbers of telogen hairs across the scalp caused by severe systemic physiological shock, high fever, major surgery, crash dieting, toxic drug reactions, or severe emotional trauma. | Follicles usually resume normal cycling once the underlying stressor is resolved. |
| Traction Alopecia | Mechanical hair loss caused by chronic, continuous tension and pulling on hair roots from tight braiding, cornrows, weaves, tight ponytails, or heavy hair extensions. | Can cause permanent follicle scarring if hairstyles are not altered promptly. |
3. Structural Hair Shaft Disorders & Abnormalities
Structural disorders involve physical alterations, genetic defects, or mechanical damage to the hair shaft:
┌─────────────────────────────────────────────────────────────────────────────┐
│ STRUCTURAL HAIR SHAFT DISORDERS │
├─────────────────────────────────────────────────────────────────────────────┤
│ • Canities: Technical term for gray/white hair (Congenital vs Acquired) │
│ • Ringed Hair: Alternating bands of gray and pigmented hair along shaft │
│ • Hypertrichosis (Hirsuties): Abnormal excessive terminal hair growth │
│ • Trichoptilosis: Technical term for split ends (Cure: Cutting ends) │
│ • Trichorrhexis Nodosa: Knotted hair with nodular swellings along shaft │
│ • Monilethrix: Technical term for beaded hair (breaks between beads) │
│ • Fragilitas Crinium: Technical term for brittle, fragile hair │
└─────────────────────────────────────────────────────────────────────────────┘
Detailed Shaft Pathology
- Canities: Technical term for gray or white hair resulting from melanin pigment loss.
- Congenital Canities: Exists at or before birth, occurring predominantly in albinos or individuals born with hereditary localized patches of white hair (piebaldism).
- Acquired Canities: Develops naturally with aging, genetic predisposition, severe prolonged illness, or extended psychological distress.
- Ringed Hair: A rare genetic condition characterized by alternating bands of pigmented and gray hair visible throughout the length of the hair strand.
- Hypertrichosis (Hirsuties): Abnormal condition of excessive growth of terminal hair in body areas that normally grow only fine vellus hair (e.g., mustache/beard growth on women, excessive back hair). Treated cosmetically via waxing, tweezing, sugaring, electrolysis, or laser hair removal.
- Trichoptilosis: Technical term for split ends. Occurs when the protective cuticle is worn away by physical friction, thermal heat, or chemical over-processing, causing cortex fibers to fray longitudinally. The only permanent remedy is trimming the damaged ends off; conditioning treatments only temporarily glue the splits together.
- Trichorrhexis Nodosa: Technical term for knotted hair. Characterized by microscopic nodular swellings along the hair shaft where cortex fibers have fractured and pushed outward like tiny brushes. The hair breaks cleanly at these weak nodes. Requires gentle handling, cessation of harsh chemicals, and rich moisturizing treatments.
- Monilethrix: Technical term for beaded hair. A genetic disorder where the hair shaft exhibits alternating constrictions and bead-like swellings. The hair is fragile and breaks easily between the nodes, leaving short, stubby patches.
- Fragilitas Crinium: Technical term for brittle hair. Hairs are extremely weak, splitting or snapping along their length from minimal tension.
4. Servicing Non-Contagious Conditions
None of the conditions in this section is contagious, so none of them requires refusing the client. What they require is modification and honesty.
| Condition | Service modification |
|---|---|
| Pityriasis capitis simplex (dry dandruff) | Medicated or anti-dandruff shampoo, gentle scalp manipulations, avoid harsh clarifying products. Chemical services are usually fine on intact skin |
| Pityriasis steatoides (greasy, inflamed) | Refer to a physician. Do not perform chemical services over inflamed or crusted scalp |
| Androgenetic alopecia | Service normally. Cutting and styling to create the appearance of density; avoid heavy chemical stress; discuss realistic expectations honestly |
| Alopecia areata | Refer. Service the remaining hair gently; avoid any chemical service over affected skin |
| Traction alopecia | Stop the cause. Advise against tight braids, weaves, extensions and tightly pulled styles. Reversible only if tension stops before the follicle is destroyed |
| Telogen effluvium | Refer. Gentle handling; avoid chemical services until shedding settles |
| Trichorrhexis nodosa, trichoptilosis | Cut off the damage; reconstructive conditioning; reduce heat and chemical load |
| Canities (grey hair) | Not a disorder. Grey hair is often more resistant to colour and may need pre-softening or a longer processing time |
The honesty duty
Chapter 1's ethics section requires transparency about realistic outcomes. Hair loss is the area where that duty is most tested, because clients want reassurance and products promise a great deal.
- You may not diagnose. Naming a condition is a medical act barred by 19 NYCRR § 160.27(c).
- You may describe what you see. "The loss is in a defined round patch with smooth skin, rather than diffuse across the whole scalp" is an observation, not a diagnosis.
- You may not promise regrowth, and you may not sell a product as a treatment for a condition.
- You may explain what a service will and will not do. A cut can create the appearance of density; it cannot create hair.
- You should refer any sudden, patchy, rapidly progressing or inflamed hair loss, and any hair loss accompanied by scalp symptoms.
Traction alopecia deserves special emphasis in a state where braiding, locking, weaving and extension work are explicitly within the licence under GBL § 400(5). It is the one significant alopecia that a cosmetologist can cause, and the one a cosmetologist can most directly prevent — by refusing to install a style at a tension that pulls the hairline, by checking the hairline at every maintenance appointment, and by advising rest periods between protective styles.
What is the technical medical term for gray or white hair resulting from the loss of melanin pigment in the cortex?
Which scalp condition is characterised by dry, flaky, greyish-white scaling and is the most common form of dandruff?
A client who has worn tight braided extensions for several years shows thinning and recession along the frontal hairline. What is the professional response?