Home Drug Doses Insulin
💉 Insulin · Type 1 & Type 2 Diabetes · Basal-Bolus · Correction Factor

Insulin Dose Calculator

India · Basal-Bolus · Correction Factor · Sliding Scale · Glargine · NPH · Regular · Aspart · Lantus · Actrapid · Insulatard

TDD: 0.3–1 unit/kg/day ISF = 1800 ÷ TDD 50% basal + 50% bolus Adjust by SMBG

Insulin Dose Calculator

Insulin Dose
TDD
ISF (1800 rule)
Basal
Per-meal bolus
📊 Basal-Bolus Breakdown
📋 Sliding Scale — Regular/Rapid Insulin
Blood glucose (mg/dL)Insulin dose (units)Action
⚠️
🚫
ℹ️
💉 Insulin types — India

Rapid-acting — onset 15min, peak 1–2h

Aspart: NovoRapid · Novorapid FlexPen

Lispro: Humalog · Lupsulin R

Short-acting (Regular) — onset 30min, peak 2–4h

Actrapid · Huminsulin R · Wosulin R

Intermediate (NPH) — onset 2h, peak 4–8h

Insulatard · Huminsulin N · Wosulin N

Long-acting (Basal) — onset 2–4h, no peak

Glargine: Lantus · Basaglar · Glaritus

Detemir: Levemir

Degludec: Tresiba

🩸 Target glucose ranges
Fasting (general)80–130 mg/dL
Post-meal 2h<180 mg/dL
Bedtime100–150 mg/dL
ICU target140–180 mg/dL
PregnancyFasting <95; post-meal <140
Elderly (relaxed)Fasting <150 mg/dL
⚠️ Hypoglycaemia rule

BG <70 mg/dL: Treat with 15g carbs. Recheck in 15 min. Repeat if still <70.

BG <54 mg/dL / unconscious: IV dextrose 25ml D50 immediately.

⚠️ Never give insulin correction for BG <100 mg/dL

⚠️ Hold bolus if patient not eating

Insulin Therapy — Clinical Guide India

Insulin therapy is essential for all patients with Type 1 diabetes and is progressively required by the majority of patients with Type 2 diabetes as β-cell function declines over time. India has one of the highest burdens of diabetes globally (estimated 77 million adults with T2DM, ICMR 2023) and insulin therapy is widely available through government and private channels. However, insulin initiation anxiety — both from patients and physicians — is a significant barrier to timely intensification of therapy in India. Understanding the 1800 rule (Insulin Sensitivity Factor), basal-bolus concepts, and correct injection technique is essential for effective diabetes management.

Total Daily Dose — the foundation

All insulin calculations begin with the Total Daily Dose (TDD). Starting TDD by weight: Type 1 diabetes: 0.4–0.5 units/kg/day initially (honeymoon phase: 0.2–0.3 units/kg/day). Type 2 diabetes — insulin naïve: 0.3–0.5 units/kg/day. Type 2 — poorly controlled on maximal oral therapy: 0.5–1 unit/kg/day. For a 60 kg T2DM patient: starting TDD = 60 × 0.4 = 24 units → round to 24 units (12 basal + 12 bolus split across 3 meals = 4 units per meal).

Insulin Sensitivity Factor — the 1800 rule

The ISF (Insulin Sensitivity Factor, also called correction factor) estimates how much 1 unit of rapid-acting insulin lowers blood glucose in mg/dL: ISF = 1800 ÷ TDD. For regular insulin use the 1500 rule: ISF = 1500 ÷ TDD. Correction dose = (Current BG – Target BG) ÷ ISF. Example: TDD = 40 units, ISF = 1800 ÷ 40 = 45. If BG = 270, target = 120: correction = (270–120) ÷ 45 = 3.3 → give 3 units rapid-acting. The ISF should be validated against the patient's actual glucose response and adjusted over time.

NPH vs basal analogues in India

NPH insulin (Insulatard, Huminsulin N, Wosulin N) remains widely used in India due to its significantly lower cost compared to insulin analogues. NPH requires BD (twice daily) dosing — typically pre-breakfast and pre-dinner — and has a pronounced peak at 4–8 hours, increasing nocturnal hypoglycaemia risk. Long-acting analogues (glargine: Lantus, Basaglar, Glaritus; detemir: Levemir; degludec: Tresiba) are peakless, once-daily (glargine/degludec) or once-to-twice-daily (detemir) preparations with significantly lower nocturnal hypoglycaemia. The Jan Aushadhi scheme in India now includes some biosimilar insulins at reduced cost. The NPPA has introduced price controls on insulin in India — check current government pricing for patient affordability.

Frequently Asked Questions

How do I calculate the starting insulin dose for a 70 kg T2DM patient?+
For a 70 kg T2DM patient poorly controlled on oral agents: TDD = 0.5 units/kg = 35 units/day. Basal-bolus split: Basal (50%) = 17–18 units glargine at bedtime. Bolus (50%) = 17–18 units ÷ 3 meals = 5–6 units rapid-acting before each meal. ISF = 1800 ÷ 35 = 51 mg/dL per unit. Target BG 120 mg/dL. If pre-lunch BG = 230: correction = (230–120) ÷ 51 = 2.2 → give 2 extra units. Round all doses to nearest whole number unit.
What is the difference between Lantus, Basaglar, and Glaritus?+
All three contain insulin glargine 100 units/ml (U-100) and are considered biosimilar/interchangeable products. Lantus (Sanofi) is the originator brand. Basaglar (Eli Lilly) and Glaritus (Wockhardt) are biosimilar insulin glargines manufactured in India. They have the same pharmacokinetic profile (once-daily peakless action, ~24h duration). Glaritus is significantly cheaper and manufactured locally — it is widely available in government hospitals. Clinical switching between these products is acceptable with standard precautions and monitoring.
What is the rule of 1800 and when should it not be used?+
The 1800 rule (ISF = 1800 ÷ TDD for rapid-acting; 1500 ÷ TDD for regular insulin) is a reasonable starting estimate for the correction factor but has limitations. It may underestimate ISF in very insulin-sensitive individuals (lean T1DM, active patients) and overestimate it in very insulin-resistant patients (obese T2DM, steroid use, infection/illness). Always validate against the patient's actual glucose responses. In practice, document how a known correction dose affects the patient's glucose and adjust the ISF accordingly. The ISF also changes with time of day — most patients are more insulin-resistant in the morning.
⚠️Insulin doses must be individualised based on blood glucose monitoring. These are starting estimates only. Initiation and significant adjustments should be done under medical supervision. Hypoglycaemia is the most dangerous side effect — always ensure patient and carer education before starting insulin. Verify against ADA, RSSDI, and ISPAD guidelines.

Related Tools