Acute hair felting is a rare disorder of scalp hair. In this condition, the hair becomes twisted, entangled as a hard stony mass resembling a bird's nest. Sudden hair matting has been reported earlier in the literature after vigorous use of chemical and herbal shampoos. Plica polonica is a patchy area of hair matting occurring in due course of time in neglected hair or underlying psychiatric illness. This case is interesting as the whole scalp hair matted immediately after using coconut oil and castor oil following washing. Growing long hair and taking oil bath are cultural and religious customs in South India. The high viscosity of castor oil and long hair had contributed to sudden felting of hair. This disorder of hair is irreversible and the hair should be cut off. Acute nature of this disorder will result in a serious psychological impact on the patient and the family.
Keywords: Acute hair matting; bird's nest hair; plica polonica.