dutasteride has a very long half-life (5 weeks), and so it is metabolized very slowly. dutasteride at 0.5mg daily takes several months to reach a steady state concentration in the blood. Taking a loading dose of 1.5mg a day for the first ten days, and then the usual 0.5mg a day from then on will enable the drug to build up much quicker in your body. I myself used this loading method when I began dutasteride. From looking at the graph, you can see that after ten days of the 1.5mg loading dose, the amount of dutasteride in your blood will be very close to the steady state level. If you were to take 0.5mg a day from the very beginning, it would take at least two months to reach where you'd be at after 10 days of the loading dose.