What is Anagen Effluvium? Anagen Effluvium is a specific form of hair loss that occurs when the growth phase of hair follicles is disrupted. This condition often leads to swift and widespread hair shedding. Factors such as certain medications and treatments, especially chemotherapy, can instigate this type of hair loss. As it affects the actively growing hairs the sudden and severe hair loss can be extremely distressing for those affected. Recognizing the signs early can be beneficial and understanding the extent and potential impact of this condition.