Lantus Penfill 100 IU/ml | Insulin Glargine Basal Insulin Cartridge

Lantus Penfill – Insulin Glargine 100 IU/ml by Sanofi

What is Lantus Penfill?

Lantus Penfill contains insulin glargine 100 IU/ml in a 3 ml cartridge format designed for compatible insulin pen devices (e.g. ClikSTAR, AllStar, JuniorSTAR). Manufactured by Sanofi (France), Lantus is one of the world's most widely prescribed basal insulins. After subcutaneous injection, the acidic glargine solution (pH 4) forms microprecipitates at physiological pH, creating a depot that releases insulin slowly over ~24 hours with no pronounced peak. This peakless profile mimics physiological basal insulin secretion, providing stable fasting and overnight glucose control with once-daily dosing. Suitable for Type 1 and Type 2 diabetes in adults and children ≥6 years.

Generic Name & Composition

Each ml: 100 IU insulin glargine. Glargine differs from human insulin at two positions: A21 asparagine → glycine (acid stability); B30 +2 arginine residues (shifts isoelectric point). The resulting molecule is soluble at pH 4 (formulation) but precipitates at physiological pH 7.4 in SC tissue — forming slow-dissolving microcrystals for prolonged peakless release over ~24 hours.

Indications

• Type 1 diabetes — basal component in basal-bolus regimen
• Type 2 diabetes — once-daily basal insulin; alone or with OADs/bolus insulin
• Adults, adolescents, and children ≥6 years
• Insulin-naïve Type 2 patients starting basal insulin therapy

How It Works — Mechanism of Action

After SC injection, the acidic glargine solution neutralises to physiological pH, causing microprecipitation and depot formation. Gradual dissolution of glargine microcrystals releases insulin monomers into the bloodstream at a slow, constant rate — producing a flat, peakless 24-hour plasma insulin profile. Glargine activates insulin receptors identically to human insulin: glucose uptake via GLUT-4, suppression of hepatic glucose production, promotion of glycogen and protein synthesis.

Dosage & Administration

Type 2 (insulin-naïve): Start 10 IU once daily at bedtime; titrate by 2 IU every 3 days targeting fasting BG ≤7 mmol/L. Type 1: Individualised; typically replaces NPH basal dose. Penfill cartridges must be loaded into a compatible reusable pen device. Inject subcutaneously (abdomen, thigh, or upper arm). Do not administer IV or IM. Do not mix with other insulins.

Side Effects

Very common: Hypoglycaemia.

Common: Injection site reactions, lipohypertrophy, peripheral oedema, weight gain.

Uncommon: Lipoatrophy, visual refraction changes at initiation.

Rare: Generalised allergic reactions, anaphylaxis.

Drug Interactions

Enhance effect: OADs, GLP-1 agonists, SGLT-2 inhibitors, ACE inhibitors, MAO inhibitors, salicylates, sulfonamides, alcohol.

Reduce effect: Corticosteroids, glucagon, thyroid hormones, growth hormone, sympathomimetics, danazol, oral contraceptives, thiazides, protease inhibitors.

Mask symptoms: Beta-blockers, clonidine, reserpine.

Contraindications

• Hypersensitivity to insulin glargine or any excipient
• Active hypoglycaemia; IV or IM administration; mixing with other insulins

Pregnancy & Lactation

Pregnancy: Limited data — consider switching to human insulin under specialist guidance. Lactation: No clinically significant infant exposure expected via breast milk.

Precautions & Warnings

• Never mix Lantus in the same syringe or pen with any other insulin — microprecipitation profile will be altered unpredictably.
• Penfill cartridges require a compatible reusable pen device — not compatible with disposable SoloStar pens.
• Rotate injection sites to prevent lipohypertrophy.
• Do not freeze. Do not expose to direct heat or sunlight.

Overdose

Hypoglycaemia. Mild: oral glucose. Severe: IV 20% dextrose or IM glucagon 1 mg. Monitor every 2–4 hours given ~24-hour duration.

Storage Instructions

• Unopened: 2–8°C. Do not freeze.
• In-use cartridge: Below 30°C. Do not refrigerate.
• Discard 28 days after first use.

Frequently Asked Questions (FAQs)

Q1: What is the difference between Lantus Penfill and Lantus SoloStar?
Both contain the same insulin glargine 100 IU/ml. Lantus Penfill is a 3 ml cartridge that must be loaded into a compatible reusable pen device (e.g. ClikSTAR). Lantus SoloStar is a disposable pre-filled pen — ready to use straight from the box. Penfill cartridges are often preferred by experienced insulin users who already have a reusable pen.

Q2: Why can't I mix Lantus with other insulins?
Lantus is formulated at pH 4. Mixing with other insulins (pH 7+) causes immediate neutralisation, disrupting the microprecipitation mechanism that creates its 24-hour peakless profile. The resulting mixture has unpredictable pharmacokinetics — dangerous for glucose control.

Q3: Is Lantus the same as glargine biosimilars?
Lantus is the originator insulin glargine by Sanofi. Biosimilars (e.g. Basalog, Glaritus) contain the same glargine molecule but are manufactured by different companies. Regulatory approval requires demonstration of biosimilarity, but switching should be done under medical supervision.

Q4: What pen is compatible with Lantus Penfill?
Lantus Penfill 3 ml cartridges are compatible with Sanofi's ClikSTAR, AllStar Pro, and JuniorSTAR reusable pen devices. Always confirm compatibility before use.

⚕ Medical Disclaimer: For educational purposes only. Lantus is Rx-only. Consult your diabetologist before changing insulin therapy. DiabetesStore.com.bd is a licensed online pharmacy.