High insulin level?

I had labs drawn, I thought just to check my thyroid function after a med change, but my doctor ordered full workup (CBC, CMP, a1c, insulin/cpep, etc). I saw the results online - everything normal, except my insulin levels were 154.2 (normal range 2.6-24.9)! My c peptide was 1.5 (fasting), so that’s most likely from synthetic insulin, from what I’m reading (insulin resistance would cause a correspondingly high c peptide). Is this normal for diabetics - normal range doesn’t apply? I don’t have a follow up scheduled with my doctor currently (again, labs were originally ordered just to check thyroid and make med change if necessary) - should I schedule one, or message her? I’m sure she’s seen these results, so I feel like they would’ve called me in if it was a problem. :confused:

ETA: I’m not on basal insulin, so this result was ~12 hours post last Novolog injection.

Insulin level lab isn’t relevant if you’re taking exogenous insulin… and insulin level labs are next to worthless even without that. What was the reference range on the c-peptide?

although I do find it interesting that the last insulin bolus was so far in the past, I don’t know how to interpret that. That’s something I’d be asking an endocrinologist (who hopefully is the one managing your thyroid labs also)

That’s what I thought, though it was also odd to me that it would be that high when I hadn’t injected anything for so long. C peptide range was 1.1-4.4. I’ve been hovering here for a while (last one was 1.4), though my non-d brother had his checked recently, and it was 1.8 or something, so not sure it’s really relevant, either.

100% agree. Discuss all the labwork with a Doctor.

I think it is a good idea to request expected lab orders about 3 weeks in advance of an upcoming appointment such that the results as a comprehensive entirety can be discussed with your Doctor.

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That’s what we usually do, but this last appointment we made a thyroid med change, and she told me we’d recheck thyroid labs in 6 weeks and she’d adjust my dose if needed - I wasn’t expecting this other stuff, or I would’ve asked for an appointment. She’s always pretty booked up, so I know I won’t be able to get in for a month or two, so I was just curious in the meantime.