How can i lose 10 pounds or more a month?

I wan't to lose at least 40 pounds with in the next 4 or 5 months. It's mostly my upper body, the weight i gained from pregnancy and munching on un healthy foods from being so stoned! I try no to eat when am stoned but then i starve my self until then! I can starve my self and nibble here and there but when i hit the joint...the pain of hunger is there! I don't get it the rest of my body is numbed..but my stomach is ALIVE and HUNGRY!!! IS there an other way or just replace my munchies attack habit with??