Suggest short-term intermittent RT-CGM for T2DM not on prandial insulin

STEP 1 — Gather Information

Confirm type 2 diabetes diagnosis, verify insulin regimen is basal-only (no prandial insulin), obtain latest A1C, assess patient willingness and ability to perform fingerstick calibrations and wear CGM sensor, and screen for contraindications (e.g., inability to afford, skin adhesive allergy, cognitive impairment, pregnancy without obstetric approval).

STEP 2 — Rule In / Rule Out

If the patient is an adult with T2DM not receiving prandial insulin → proceed to next step; otherwise, do not suggest intermittent RT-CGM (rule out).

STEP 3 — Classify or Stratify

If A1C is ≥7% and the patient is willing and able to use the device → classify as a candidate for short-term intermittent RT-CGM; otherwise, consider alternative approaches or reassess barriers.

STEP 4 — Decide

Prescribe a short-term intermittent RT-CGM regimen (e.g., 2 weeks of sensor use followed by 1 week off, repeated for 12 weeks), provide device-specific education and training (including calibration, trend interpretation, and alarm settings), schedule follow‑up visits to review CGM data and A1C, and adjust basal insulin or lifestyle recommendations based on observed glucose patterns.

Clinical Guardrails / Mimics / Pitfalls

Do not use in patients on prandial insulin; do not replace SMBG calibration with CGM alone; avoid in patients with severe hypoglycemia unawareness without supervision; do not use as a substitute for structured diabetes education; ensure patient understands sensor limitations (e.g., lag, need for confirmatory fingersticks); not indicated for pregnancy unless specifically advised; do not prescribe if patient unwilling or unable to perform required calibrations or afford supplies.

Concrete Clinical Example

A 58‑year‑old man with T2DM on basal insulin glargine only, A1C 8.2%, expresses willingness to wear a sensor and perform twice‑daily fingersticks, has no hypoglycemia unawareness, and can afford supplies. Prescribe intermittent RT‑CGM (2 weeks on/1 week off) for 12 weeks, provide education, review data at 4‑week intervals, and consider continuing if A1C drops ≥0.5% or time in range improves.

Source: Real-time continuous glucose monitors in adult outpatients, Endocrine Society Clinical Practice Guideline, 2016, DOI: 10.1210/jc.2016-2534

TODO: consider adding scripts/calc.py for the endo-rtcgm-suggest-short-term-intermittent-t2dm calculator