There can be wide variation in weight as per height and age depending on where you live and your ethnic background. However, a weight around 125 pounds would be ideal. You can however try to maintain a weight below 130 pounds to remain in the BMI range of normal weight. So, roughly you need to lose about 40 pounds. Take care!
The medical advice given should not be considered a substitute for medical care provided by a doctor who can examine you. The advice may not be completely correct for you as the doctor cannot examine you and does not know your complete medical history. Hence this reply to your post should only be considered as a guiding line and you must consult your doctor at the earliest for your medical problem.