Basaglar (Insulin Glargine): How This Long-Acting Follow-On Insulin Works and When Telehealth Is Enough

Last updated: August 19, 2026

Basaglar is insulin glargine. People also search “basaglar insulin,” “basaglar kwikpen,” and “basaglar tempo pen.” Those names point to a long-acting (basal) U-100 insulin glargine product from Eli Lilly. It is not Lantus even though both are insulin glargine U-100. It is not Semglee or Rezvoglar (interchangeable biosimilars to Lantus). It is not Toujeo (insulin glargine U-300). It is not meal-time insulin such as Humalog or NovoLog. It is not a treatment for diabetic ketoacidosis. Do not treat a pharmacy switch as a reason to change your own units without a clinician check.

This guide covers how Basaglar is usually injected, how a KwikPen differs from a Tempo Pen, why “follow-on” is not the same as an interchangeable biosimilar, and when a video visit is enough versus when you need labs or the ER. It is educational. It is not a diagnosis or a promise that any specific insulin will be prescribed.

Want a licensed clinician to review basal insulin or an A1C? Klarity Health has 2,000+ licensed providers. Many visits happen online. See online prescription options or browse conditions.

TLDR

• DailyMed lists BASAGLAR (insulin glargine) injection for subcutaneous use. Initial U.S. approval: 2015. It is a long-acting human insulin analog indicated to improve glycemic control in adults and pediatric patients with type 1 diabetes mellitus and in adults with type 2 diabetes mellitus. It is not recommended for treating diabetic ketoacidosis (DailyMed Basaglar KwikPen / Tempo Pen).
• Presentations are 100 units/mL (U-100) only: a 3 mL single-patient-use BASAGLAR KwikPen and a 3 mL single-patient-use BASAGLAR Tempo Pen. There is no Basaglar vial on this label.
• Inject under the skin once daily at any time of day, but at the same time every day. Rotate sites among the abdomen, thigh, or deltoid. Do not dilute or mix with any other insulin or solution. Do not use it in an insulin pump. Never inject into a vein.
• The FDA approved Basaglar in December 2015 as a follow-on insulin glargine product. That pathway is not the same as interchangeable biosimilar status. A pharmacist generally cannot auto-substitute Basaglar for Lantus the way Semglee or Rezvoglar may be substituted when state law allows (PMC review of follow-on insulin).
• MedlinePlus groups Basaglar, Lantus, Semglee, Rezvoglar, and Toujeo as insulin glargine products. The products are highly similar. They are not always the same carton at the counter. Always check the name on the pen (MedlinePlus insulin glargine).
• Contraindications: do not use during hypoglycemia or if you are allergic to Basaglar or an excipient. Never share a prefilled pen, even if you change the needle.
• In-use pens: MedlinePlus says opened insulin glargine pens stay at room temperature and may be used for up to 28 days after first use. Unused refrigerated stock can last until the labeled expiration date. Do not freeze it.
• Typical home glucose targets many adults use: 80 to 130 mg/dL before meals and under 180 mg/dL two hours after a meal starts. A reading under 70 mg/dL is low. If you are sick and a reading is 240 mg/dL or higher, check ketones (CDC manage blood sugar).
• Medicare covers many telehealth visits from home anywhere in the U.S. through December 31, 2027 (HHS telehealth policy). Seizure, loss of consciousness, chest pain, or blood sugar that will not come up is 911, not a video visit.

What Basaglar is trying to fix

Type 1 diabetes means the pancreas makes little or no insulin. Type 2 diabetes means the body resists insulin and often does not make enough of it. Glucose stays in the blood. Over years that raises the chance of heart disease, stroke, kidney disease, nerve damage, and eye disease. NIDDK notes some people with type 2 diabetes can control glucose with food, activity, sleep, and weight change. Many still need pills or insulin. Over time you may need more than one medicine (NIDDK insulin and medicines).

Insulin glargine replaces background insulin. MedlinePlus says it moves sugar from the blood into tissues and slows the liver from making more sugar. It does not cover the spike right after a meal. That is why type 1 regimens add a short-acting insulin at meals, and why some type 2 regimens still use meal-time insulin or an oral class.

Basaglar is insulin glargine U-100 in Lilly pens. DailyMed’s type 1 indication includes pediatric patients. The type 2 indication on this label is adults. Toujeo is a more concentrated glargine (U-300). Semglee and Rezvoglar are interchangeable biosimilars to Lantus. Basaglar is a follow-on product approved in 2015. Coverage varies by plan. Verify benefits before you assume the carton will stay the same month to month.

Typical home targets the CDC lists for many adults:

• Before a meal: 80 to 130 mg/dL
• Two hours after the start of a meal: under 180 mg/dL

Blood sugar under 70 mg/dL is low. If you are sick and a reading is 240 mg/dL or higher, check ketones. High ketones can signal diabetic ketoacidosis, which is an emergency. Basaglar is not the insulin used to treat DKA.

Related Klarity guides: Lantus (insulin glargine), Semglee and Rezvoglar, Toujeo (insulin glargine U-300), Tresiba (insulin degludec).

How the Basaglar KwikPen and Tempo Pen work

DailyMed lists two 3 mL single-patient-use pens at 100 units/mL: the KwikPen and the Tempo Pen. One pen holds 300 units. Needles are sold separately. Never share a pen, even if you change the needle.

Inject once a day at the same clock time. You can pick morning or evening. Changing the clock time without a plan can stack two basal doses too close together or leave a long gap. Rotate sites. Skip skin that is thick, lumpy, bruised, or scarred.

The solution should be clear and colorless. Do not use it if it is cloudy, colored, or has particles. Do not mix Basaglar with NPH, Regular, Humalog, or anything else in one syringe. Do not put it in a pump.

DailyMed says to individualize the dose based on metabolic needs, glucose logs, type of diabetes, and prior insulin. Monitor closely when you convert to Basaglar and during the first weeks after a switch. Do not copy a neighbor’s units.

Follow-on vs interchangeable biosimilar

Basaglar reached the U.S. market as a follow-on insulin glargine product in 2015, before the current interchangeable-biosimilar pathway for insulin was fully in play. Semglee and Rezvoglar later received interchangeable biosimilar designations versus Lantus. That extra FDA finding can allow pharmacy-level substitution for Lantus when state law allows. Basaglar does not carry that interchangeable designation versus Lantus. Your plan may still prefer Basaglar, Lantus, Semglee, or another glargine. A video visit can review the name on the carton. It cannot force a PBM to keep one brand.

Cleveland Clinic groups insulin glargine U-100 products such as Lantus and Basaglar on the long-acting chart. Follow your own prescription for timing and units, not a chart meant as a class overview (Cleveland Clinic injectable insulin chart).

Storage, missed doses, and common mix-ups

Keep unused pens in the refrigerator. Do not freeze them. MedlinePlus: unrefrigerated unused vials or pens can be used within 28 days; opened pens stay at room temperature for up to 28 days after first use. Do not put an opened pen back in the fridge. Discard insulin that sat in a hot car.

Ask your clinician what to do if you miss a dose before you start. Writing that plan down beats guessing at 2 a.m. An extra basal dose stacked on yesterday’s dose can drop glucose hours later.

Check the pen name every time. Basaglar, Lantus, Semglee, Rezvoglar, and Toujeo can sit near each other in a fridge. Toujeo is U-300. A unit-for-unit swap with U-100 glargine is not automatic.

Side effects and when to get help

DailyMed lists common reactions (≥5%) with insulin glargine products: hypoglycemia, allergic reactions, injection site reaction, lipodystrophy, pruritus, rash, edema, and weight gain. Hypoglycemia can be life-threatening. Risk goes up when the dose changes, when you add other glucose-lowering drugs, when meals or activity change, and in people with kidney or liver impairment or hypoglycemia unawareness.

Call emergency services for seizure, loss of consciousness, or glucose that will not rise after fast carbs. DailyMed also flags severe allergy (anaphylaxis), low potassium, and fluid retention or heart failure when insulin is used with a thiazolidinedione such as pioglitazone or rosiglitazone. Report suspected reactions to Eli Lilly at 1-800-LillyRx or FDA MedWatch.

When telehealth is enough, and when it is not

A licensed clinician on video can review logs, A1C, current pens, hypoglycemia history, and whether a basal change or a lab order makes sense. Klarity Health has 2,000+ licensed providers. Many visits happen online. Medicare covers many telehealth visits from home through December 31, 2027.

Go in person or to the ER for suspected DKA, severe hypo you cannot treat at home, chest pain, or a new severe rash with trouble breathing. Insulin starts and brand switches need closer glucose checks. Coverage for a specific pen may vary by plan. Verify benefits before you book if cost is the reason for the visit.

Ready to review basal insulin with a licensed clinician? See online prescription options or browse conditions.

FAQ

Is Basaglar the same as Lantus?

Both are insulin glargine U-100. They are not automatically the same product at the pharmacy. Basaglar is a 2015 follow-on product. Lantus is the reference brand. Semglee and Rezvoglar are interchangeable biosimilars to Lantus. Check the pen name and your plan’s preferred product.

Can I mix Basaglar with Humalog?

No. DailyMed says do not dilute or mix Basaglar with any other insulin or solution. Give meal-time insulin as a separate injection.

Can I put Basaglar in a pump?

No. MedlinePlus says do not use insulin glargine products in an external insulin pump. Basal glargine is a once-daily under-the-skin shot.

Does insurance cover Basaglar?

Coverage varies by plan and formulary year. Some plans prefer Basaglar. Others prefer Lantus, Semglee, or another basal. Verify benefits before you assume the copay.

This article is for education. It is not medical advice, a diagnosis, or a guarantee of insurance coverage. Coverage and prescribing decisions vary. Confirm benefits and talk with a licensed clinician before you change insulin.