Trichorrhexis nodosa is a defect in the hair shaft characterized by thickening or weak points (nodes) that cause the hair to break off easily. This group of conditions contributes to the appearance of hair loss, lack of growth, and damaged-looking hair.

Among the symptoms (and signs) for this condition are the following:

This condition is not dangerous but may affect self-esteem.

Trichorrhexis may have a genetic basis but appears to be precipitated by environmental factors. Among Caucasians the defect often appears at the ends of the hair shaft with splitting of the ends, thinning and whitish discoloration.

These conditions are directly related to environmental causes such as "perming", blow drying, aggressive hair brushing, and excessive chemical exposure.

In some cases, trichorrhexis nodosa may be caused by an underlying disorder such as argininosuccinic aciduria, Menkes' kinky hair syndrome, Netherton's syndrome, hypothyroidism, or trichothiodystrophy.

Examination of the hair shafts with a microscope may reveal changes of trichorrhexis nodosa.

Avoid aggressive brushing and grooming, strong chemicals, permanents, straightening, and similar hair-damaging habits.