Hi @sec1205 That’s a fairly high tacro trough considering the low dosage your’re on. What is the goal your transplant team is shooting for? One of the side effects of a higher tacro trough is mental status change.
You had only mentioned being on progesterone along with the low dose of tacro. But if you’re also on Cellcept and or other meds too, there can be an interaction in medications where one will cause another to not metabolise through the system as quickly, causing a higher trough.
I had that happen when switching from an IV form of antifungal to oral Pozaconozol. My normal trough was 7. With the same dosage of tacro but the new oral med, my trough zoomed up to over 21 + within a couple of days! I was a royal mess and my kidneys went into faiure.
Have you spoken with your team about adjustments to the tacro?

I am 18 months post. I am currently taking 3mg in the morning & 2mg in the evening and my Tacro level is set & fluctuating between 3 & 5. Yours is somewhat on the high side vis-a-vis your current dosage. May be it is because of this fact that your doctors kept the dose so low so early meaning taking a higher dosage than you do now may further jack up the Tac Level into the teens. Like you said it could be due to your unique (i.e. individualized) physical response to Tacrolimus. I also take 2 X 500mg cellcept.
So far I had no mental or emotional side effects but I feel that I am in the initial stages of developing gastric problems. My main concern is the fatigue I am experiencing for the last 4-5 months. I could not shake it off & my transplant team is telling me that my liver is functioning well & I need to search for the culprit elsewhere with my primary care doctor.