May search for a particular kind of hair to pull, pull out hair in a specific way, or visually examine or manipulate the hair after. Preceded or accompanied by feelings of anxiety, boredom, tension, gratification, pleasure, or relief. Varying degrees of awareness.
Some display automatic behavior. Some experience an "itch-like" or tingling sensation that is alleviated by the act. Pain does not usually occur. Patterns of hair loss highly variable. Areas of complete alopecia are common. Eyebrows and eyelashes may be absent. Does not usually occur in the presence of others except immediate family. Some have urges to pull hair from others and may try to do so. Some may pull from pets, dolls...
Some may deny it. Most have 1+ other body-focused repetitive behaviours, including skin picking, nail biting, and lip chewing.