The duration of hair loss can vary depending on the underlying cause. In some cases, hair loss may be temporary and may resolve on its own, while in other cases it may be permanent. Temporary hair loss can last for a few months and may be caused by factors such as stress, hormonal changes, certain medications, or a nutritional deficiency. Once the underlying cause is identified and addressed, hair growth can usually resume and the hair loss may stop. However, some types of hair loss are permanent, such as androgenetic alopecia (male or female pattern baldness), which is the most common cause of hair loss in both men and women. This type of hair loss is caused by genetic and hormonal factors and can lead to progressive thinning of the hair over time. Hair loss due to scarring from injury or certain medical conditions, such as lupus or lichen planopilaris, may also be permanent.