I received two 40‑mg intra‑articular cortisone injections (one in each knee) 36 hours ago; my overnight blood glucose is around 300 mg/dL while using insulin glargine (Lantus) 18 U daily with a carbohydrate‑to‑insulin ratio of 1 U per 12 g carbs and a high correction factor—should I increase the basal insulin dose, tighten the carb ratio, and adjust the correction factor?

Immediate Insulin Adjustment for Cortisone‑Induced Hyperglycemia

Increase your Lantus dose immediately to 24–26 units (a 33–44% increase from 18 units) and tighten your carbohydrate ratio to 1:8–1:10 grams while increasing your correction scale by 50% to manage the transient hyperglycemia caused by intra‑articular corticosteroid injections.

Understanding Cortisone‑Induced Hyperglycemia

• Intra‑articular corticosteroid injections cause acute hyperglycemia lasting 2–7 days, with peak glucose elevations typically occurring 24–72 hours post‑injection and values reaching as high as 300–500 mg/dL in patients with diabetes 1, 2, 3.
• The hyperglycemic effect is transient and self‑limited, resolving within 1 week as the steroid is absorbed and metabolized 2, 3.
• Your current overnight glucose readings in the 300s mg/dL range are consistent with the expected peak effect occurring 36 hours after receiving 80 mg total triamcinolone (40 mg per knee) 2, 3.

Immediate Basal Insulin Adjustment

• Increase Lantus from 18 units to 24–26 units once daily (approximately 33–44% increase) to counter the steroid‑induced insulin resistance 4, 5.
• This aggressive upfront increase is necessary because corticosteroids typically require 40–60% higher insulin doses than baseline to maintain glycemic control 4, 5.
• Administer the increased Lantus dose at your usual time (typically bedtime) to provide 24‑hour basal coverage 6.
• Do not delay this adjustment; the hyperglycemia you are experiencing (300s mg/dL) warrants immediate intervention rather than gradual titration 4.

Carbohydrate Ratio Adjustment

• Tighten your carbohydrate‑to‑insulin ratio from 1:12 to 1:8–1:10 grams (approximately 20–50% increase in prandial insulin) to adequately cover meals during the steroid effect 5.
• This means you will now give 1 unit of rapid‑acting insulin for every 8–10 grams of carbohydrate instead of every 12 grams 5.
• For example, a 60‑gram carbohydrate meal that previously required 5 units (60÷12) will now require 6–7.5 units (60÷10 or 60÷8) 5.

Correction Scale Adjustment

• Increase your correction insulin doses by approximately 50% to address the elevated glucose readings 4, 5.
• If your current "high correction scale" provides 1 unit for every 50 mg/dL above target, temporarily adjust to 1 unit for every 30–40 mg/dL above target 4.
• Use the following simplified correction protocol in addition to your scheduled prandial insulin 4:
  • Pre‑meal glucose 201–250 mg/dL → add 2 units rapid‑acting insulin
  • Pre‑meal glucose 251–350 mg/dL → add 4 units rapid‑acting insulin
  • Pre‑meal glucose >350 mg/dL → add 6 units and contact your provider

Monitoring Protocol

• Check blood glucose every 2–4 hours for the first 48 hours after implementing these adjustments to identify patterns and prevent hypoglycemia 4, 5.
• Measure glucose before each meal, 2 hours after meals, at bedtime, and upon waking to guide further dose adjustments 4.
• Target a fasting glucose of 80–130 mg/dL and daytime glucose of 140–180 mg/dL during this acute period 4.

Tapering Protocol (Days 4–7)

• Begin reducing insulin doses on day 4–5 as the steroid effect wanes and glucose values start normalizing 5, 3.
• Reduce Lantus by 2 units every 2–3 days once fasting glucose consistently falls below 130 mg/dL 4, 5.
• Return to your original 1:12 carbohydrate ratio once pre‑meal glucose readings stabilize in the 100–150 mg/dL range 5.
• Resume your baseline correction scale when daytime glucose values no longer exceed 200 mg/dL 4.
• By day 7–10, you should be back to your pre‑injection insulin regimen of Lantus 18 units with 1:12 carb ratio 2, 3.

Hypoglycemia Prevention

• If any glucose reading falls <70 mg/dL, immediately reduce the implicated insulin dose by 10–20% without waiting 4, 5.
• Treat hypoglycemia with 15 grams of fast‑acting carbohydrate (4 glucose tablets or 4 oz juice), recheck in 15 minutes, and repeat if needed 4.
• The risk of hypoglycemia is highest between days 5–7 as the steroid effect resolves but insulin doses remain elevated; close monitoring during this transition is critical 5, 3.

Critical Pitfalls to Avoid

• Do not maintain your baseline insulin doses when glucose consistently exceeds 250 mg/dL; this reactive approach is inadequate for steroid‑induced hyperglycemia 4, 5.
• Do not rely solely on correction insulin without adjusting your scheduled basal and prandial doses; correction doses must supplement, not replace, scheduled insulin 4.
• Do not delay dose reductions once the steroid effect begins to wane (typically day 4–5); failure to taper insulin as glucose normalizes is the most common cause of hypoglycemia in this setting 5, 3.
• Never use rapid‑acting insulin at bedtime as a sole correction dose, as this markedly raises nocturnal hypoglycemia risk 4.

When to Contact Your Provider

• If glucose remains >300 mg/dL after 48 hours despite the above adjustments 4.
• If you experience any glucose <70 mg/dL that does not respond to 15 grams of carbohydrate within 15 minutes 4.
• If you develop nausea, vomiting, or abdominal pain with glucose >250 mg/dL (possible ketoacidosis) 4.
• If you are uncertain about dose adjustments or experience wide glucose variability (swings >100 mg/dL between readings) 4.

Expected Clinical Outcomes

• With these adjustments, your overnight glucose should fall to 140–180 mg/dL within 24–48 hours and normalize to <130 mg/dL by day 5–7 4, 3.
• The total duration of hyperglycemia is typically 5–7 days, with complete resolution by day 10 in most patients 2, 3.
• Properly implemented dose adjustments do not increase overall hypoglycemia risk when tapered appropriately as the steroid effect resolves 4.