I am on 2 units of Nutropin. My endo.sends me for igf1 testing every 3 or 4 months. I dont understand the target range for my age (71) how does one know if you are at the correct dose? ## There can be many variations to what can be considered normal for the igf1, depending on age, health and etc. However, for someone between the ages of 70 and 74, the target ranges for females are generally 57 to 237 and for males 46 to 207 and your doctor doesn't usually look for a strict match, a little bit outside of those numbers would still be considered okay. Your doctor should let you know if your levels aren't considered good and if you need to make any medication dosing change. Are there any other questions or comments?