Hello, Thank you for your question. The most common cause of hair loss is a condition called androgenetic alopecia. This condition is also known as male pattern baldness when it happens in men and female-pattern hair loss when it happens in women. Andogenetic alopesia can look different in men and women. Women often have a thinning hair on the top of the scalp, but usually do not lose all of the hair there. Another common cause of hair loss is called alopecia areata. This type of hair loss happens when the body s infection-fighting system gets confused and starts to attack the parts of the skin where hair grows. People with alopecia areata have big, usually round spots of hair missing. But there are more many other reasons for hair loss. some medical conditions and even some medicines can also cause hair loss. Most people with hair loss do not need tests. But your doctor might do tests to make sure your hair loss is not caused by a hormonal problem or another medical condition. Hair loss treated depends on what type of hair loss you have. If your hair loss is caused by a health problem, treating that problem can help. Other types of hair loss are treated with medicines that go on the scalp or that come in pills. Sometimes surgery is used to treat people with areas of hair that cannot grow back. See your doctor if you are not sure why you are losing our hair, your hair loss occurs suddenly, you also have itching or pain on your scalp, you also dont feel well or feel very tired. Losing your hair can be very tough. If you feel sad or anxious because of your hair loss, speak to your doctor. He or she can help you get the support you need. Hope I have answered your query. Let me know if I can assist you further. Best regards, Dr. Heang Chan Raksmey, General and Family physician.