Excessive consumption of cow milk and menorrhagia are the two most common causes of iron deficiency anaemia (IDA) in children. However, there have been reported cases of parasitic infestation causing IDA. Pediculus humanus survives on human blood, and prolonged blood loss causes anaemic symptoms. In the current case report, a 10-year-old girl complained of pallor and dizziness. During her physical examination, a head lice infestation was discovered. The patient had no history of chronic illness and used to eat a normal diet that was high in iron. Her haemoglobin level was measured to be 4 g/dl. Doctors determined that the severe iron deficiency was caused due to the head lice infestation. To reach the required haemoglobin level, she was admitted to the hospital and given a blood transfusion. Her head was washed with permethrin 1% shampoo, which removed over 60% of the lice in a single wash. She was instructed to wash her hair with the shampoo again after seven days.