Or repetitive hair pulling.  Previously classified as an impulse control disorder, ie a sense of tension that is only “satisfied” when hair is pulled out. However, many children do not get this tension and gratification so in DSM-V trichotillomania is included among obsessive-compulsive and related disorders.

Dutch cohort mostly girls, literature says no gender difference!   Nail biting can co-exist, as can stereotypies.  Many kids will also eat their hair once it is pulled out.  Most common age of onset is in early adolescence (9-13 years), but frequently occurs in early childhood, even as early as 12 months of age.  Triggering factors identified include concerns about physical appearance, family and school issues, and concurrent illness.  Parents sometimes also pull their hair, so maybe (partly) learned.

Two distinct types of trichotillomania described: automatic and focused

  • Automatic – outside of own awareness, may not recall actual pulling, but may admit to ‘playing with their hair’ or may have been noted to pull their hair in a distracted state.  Children tend to fall into this category.
  • Focused – aware, in response to negative emotion or urges

Parents often miss the hair pulling and only present when hair clumps noticed on surfaces (esp bed –  presumably due to pulling in sleep) or bald patches appear.

On Examination

Exclamation mark hairs (thin proximally, at scalp, normal distally), usually thought of being evidence of alopecia areata, may be seen, so not very predictive.  Pull test – gentle traction on about 20 hairs in 3 different locations.  Positive if more than 5 hairs extracted – suggests active alopecia areata.  You may miss dormant alopecia, but in that case hair regrowth should occur.