This doesn’t really fall under the "med resistance" topic - but I thought it might be interesting to you.

My son, a 6 year old with SWCAH has always struggled with oversuppression. His 17OHP has not been over 50 ng/dl (normal 3-90) for the last several years. His 17OHP is low despite the fact he is on a very low dose of Cortef (8.75mg/day or 7 mg/m2/day).

On his last endo visit we saw a different endo because his first doc is on leave. This endo had what I think is a very interesting way of analyzing my son’s bloodwork.

The labs show 17ohp elevated at 1870, however, his andro was well within the range at 24 nano/ml (range of 8-50). (His last ACTH was also well within the range at 25 with a range of 10-60)

This endo said that althought the 17OHP is elevated, it doesn’t appear to be spilling over into his androgen pathway. The 17OHP itself doesn’t have a negative impact, it is the high androgens that cause the problems. Because he has no clinical signs of undersuppression and nothing but the 17OHP could indicate that, the doc recommended keeping his dose the same.

I was delighted when this doc said to leave his dose the same. In the past we have been told to increase it when the 17OPH jumps and then 3 months later the 17OHP  is back to <10 and he is showing signs of oversuppression.

This discussion of 17OHP alone as an indicator triggered a memory for me of something I was told years ago - a different endo told me she finds that 17OHP is quite volatile. It can rise quickly with a bad blood draw or in times of stress. In my son’s case, they usually have to search for a long time and then poke him several times. The whole fiasco can last as long as 45 minutes and he screams and pleads at the top of his lungs the entire time. I’m very interested to see what happens to his levels at the next draw, particularly if it isn’t as bad as normal.

I thought this might interest you especially if your doc is only looking at 17OHP levels. It might be helpful to get a bigger picture and see if it really is undersuppression.