Levemir (Insulin Detemir): How This Long-Acting Insulin Works and When Telehealth Is Enough

Last updated: August 18, 2026

Levemir is a brand name for insulin detemir, a long-acting (basal) insulin analog. Clinicians use it to improve blood sugar control in adults and children with diabetes mellitus. People also search “Levemir insulin,” “insulin detemir,” “Levemir FlexPen,” and “Levemir FlexTouch.” Those names point to the same molecule. Levemir is not a meal-time insulin, not an insulin pump cartridge, and not a treatment for diabetic ketoacidosis.

This guide covers how Levemir is usually injected, how once-daily and twice-daily schedules differ, what the FDA label says about starting doses, what happened after Novo Nordisk planned a U.S. discontinuation, 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. If you still have leftover Levemir, do not change brands or units on your own.

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

• Insulin detemir (Levemir) is a long-acting insulin for type 1 and type 2 diabetes. In type 1 diabetes it must be paired with a rapid- or short-acting insulin. It is not given in a vein or an insulin pump (MedlinePlus insulin detemir; FDA Levemir label).
• Mayo Clinic describes insulin detemir as a long-acting insulin that works slowly over about 24 hours. Inject it under the skin of the abdomen, upper arm, or thigh. Rotate sites. Do not inject into a vein or muscle (Mayo Clinic insulin detemir).
• FDA label: inject once daily with the evening meal or at bedtime, or split into two daily doses. For type 2 adults not already on insulin, the recommended start is 10 units (or 0.1 to 0.2 units/kg) once daily in the evening or divided twice daily. Switching from insulin glargine or NPH can start unit-to-unit; some type 2 patients need more detemir than NPH. Do not dilute or mix Levemir with any other insulin.
• Levemir is U-100 (100 units/mL) in a 10 mL vial or 3 mL FlexPen. Novo Nordisk told FDA on November 8, 2023, that it planned to discontinue Levemir FlexPen and vials in the United States, with FlexPen supply disruption expected mid-January 2024, FlexPen discontinuation April 1, 2024, and vial discontinuation December 31, 2024 (MassHealth Prescriber e-Letter, Dec 2023; Reuters). There is no commercial biosimilar for insulin detemir. Remaining stock and pharmacy supply vary. A clinician should map any switch to another basal insulin.
• Do not use Levemir during a low-blood-sugar episode or if you are allergic to insulin detemir. Never share a pen or needle. Combining insulin with a TZD (pioglitazone, rosiglitazone) can cause fluid retention and heart failure.
• 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 (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 Levemir 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 detemir 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.

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. Levemir is not the insulin used to treat DKA.

Related Klarity guides: Tresiba (insulin degludec), Lantus (insulin glargine), type 2 diabetes medication, SGLT2 inhibitors, sulfonylureas, DPP-4 inhibitors, TZDs, and meal-time diabetes pills.

How Levemir is usually taken

Levemir is a clear, colorless solution injected under the skin. MedlinePlus and FDA adult directions:

• Once a day with the evening meal or at bedtime, or twice a day (morning plus evening meal, bedtime, or about 12 hours after the morning dose). Keep the clock time consistent.
• Sites: abdomen, thigh, or upper arm. Rotate sites. Skip red, swollen, itchy, or thickened skin. Skip areas of lipodystrophy or cutaneous amyloidosis.
• Do not mix or dilute Levemir with any other insulin or solution. Do not put it in a vein or an insulin pump.
• Never use it during hypoglycemia or if a fingerstick is already low.
• Prime a pen before each injection. FlexPen dials in 1-unit increments. Use extra caution if you rely on audible clicks because of vision problems.
• Never share a FlexPen, syringe, or needle, even if you change the needle.

FDA starting doses (your clinician still individualizes):

• Type 1, insulin-naive: about one-third to one-half of total daily insulin as Levemir; the rest as short-acting meal insulin. A common first total daily insulin estimate is 0.2 to 0.4 units/kg.
• Type 2, not yet on insulin, not controlled on orals or a GLP-1: 10 units (or 0.1 to 0.2 units/kg) once daily in the evening or split twice daily.
• Switch from insulin glargine: unit-to-unit, then titrate.
• Switch from NPH: unit-to-unit is allowed; some type 2 patients needed more Levemir than NPH in a trial.

Missed-dose rule from MedlinePlus: inject the missed dose as soon as you remember that same day. Skip it if it is almost time for the next dose. Do not double up. Then call the clinic, because the next 24 hours of meal insulin and snacks may need a plan.

U.S. supply: why people still search Levemir

Novo Nordisk announced a U.S. discontinuation of Levemir. Reuters reported the November 8, 2023 company notice, citing manufacturing constraints and declining use. MassHealth summarized the FDA-facing plan: FlexPen supply disruption expected mid-January 2024, FlexPen discontinuation April 1, 2024, and vial discontinuation December 31, 2024. MassHealth also noted there were no commercially available biosimilars or authorized generics for insulin detemir. Alternative long-acting options on that Medicaid list included Lantus, Toujeo, and Tresiba without prior authorization in that program, and Basaglar or Semglee with prior authorization. Other plans use different formularies.

If a pharmacy cannot fill Levemir, that is a clinical switch, not a same-click swap. Glargine U-100, glargine U-300 (Toujeo), and degludec (Tresiba) do not share one conversion table you should invent at home. Coverage may vary by plan. Verify benefits before you assume a new basal insulin is on formulary.

Who should not use Levemir

FDA contraindications: an active low-blood-sugar episode, or known hypersensitivity to insulin detemir or any Levemir excipient (reactions have included anaphylaxis).

Other label cautions:

• Any change in insulin type, brand, strength, injection site, or delivery method needs closer glucose checks. Hyperglycemia and hypoglycemia both happen during switches.
• Renal or hepatic impairment, missed meals, extra activity, or alcohol raise hypoglycemia risk. Beta-blockers and similar drugs can hide low-sugar warning signs.
• All insulins can drop potassium. People on potassium-lowering drugs need a clinician watching labs.
• Insulin plus a TZD can cause fluid retention and heart failure. Watch swelling, sudden weight gain, and shortness of breath.
• Mayo Clinic notes pediatric studies have not shown age-specific problems that would block use in children with type 1 or type 2 diabetes, and geriatric studies have not shown age-specific limits in older adults. Breastfeeding data are limited; weigh benefit and risk with the clinician.

Side effects people actually feel

The most important risk is hypoglycemia. Treat a reading under 70 mg/dL the way your clinician taught you (often 15 grams of fast carbohydrate, then recheck). If you use acarbose as a meal pill, use glucose tablets, not juice, for a low. Seizure or loss of consciousness is emergency glucagon plus 911.

FDA lists other Levemir reactions: allergic reactions, injection-site reactions, lipodystrophy, rash, and pruritus. Adult type 1 trials also commonly reported upper respiratory infection, headache, pharyngitis, influenza-like illness, and abdominal pain. Those trial rates describe study groups; they are not a prediction for you.

Severe generalized allergy, including anaphylaxis, can occur. Stop the insulin and get emergency care if you have trouble breathing, widespread hives, or swelling of the face or throat.

When a video visit is enough

A licensed clinician can often do this online:

• Review home logs, CGM exports, A1C, kidney labs, and current orals or GLP-1s.
• Decide whether leftover Levemir still makes sense, or whether a switch to another basal insulin is safer given supply.
• Teach pen technique, site rotation, and a sick-day ketone plan.
• Write or renew a prescription when it is medically appropriate. Klarity does not promise a specific brand.

Medicare patients can receive many non-behavioral telehealth visits from home anywhere in the United States through December 31, 2027. Commercial coverage for video visits may vary. Confirm benefits before you book.

Go in person or to the ER instead when you have:

• Glucose that stays under 70 mg/dL after treatment, seizure, or confusion
• Glucose 240 mg/dL or higher with ketones, vomiting, or deep breathing
• Chest pain, one-sided weakness, or sudden vision loss
• Signs of a severe insulin allergy

Klarity Health is a telehealth practice with 2,000+ licensed providers. It is not an emergency department and not a pharmacy coupon program.

Insurance, cost, and what “coverage” actually means

A plan may list a basal insulin as preferred, non-preferred, or excluded. Prior authorization is common. Because Levemir supply in the U.S. has been winding down, many plans now steer members to glargine or degludec. That is a formulary and supply fact, not a medical judgment you should copy from a blog.

Coverage varies by plan. Verify benefits before you assume any insulin is covered. Klarity cannot promise that your insurer will pay for a visit, a lab, or a specific brand.

How this fits with pills you may already take

Type 2 care often stacks metformin, an SGLT2 inhibitor, a DPP-4 inhibitor, a sulfonylurea, a TZD, or a GLP-1 before or alongside basal insulin. Meal-time pills such as acarbose or repaglinide change how you treat a low. A TZD plus any insulin needs a heart-failure watch. Bring the full list, including over-the-counter sleep aids and steroids, to the visit.

FAQ

Is Levemir the same as Lantus or Tresiba?

No. All three are long-acting basal insulins. Levemir is insulin detemir and may be once or twice daily. Lantus is insulin glargine U-100, usually once daily. Tresiba is insulin degludec, usually once daily with a longer miss window. Unit counts do not automatically transfer.

Can I still get Levemir in 2026?

U.S. commercial supply was scheduled to end after the 2024 vial date. Some leftover stock, compounding, or non-U.S. supply may exist, but you should not count on a routine retail fill. Ask the pharmacy and the clinician the same week.

Can I mix Levemir with NovoLog in one syringe?

No. The FDA label says do not dilute or mix Levemir with any other insulin or solution.

Does insurance cover Levemir or a switch?

It depends on the plan and on whether the product is still in the supply chain. Many plans now prefer another basal insulin. Verify benefits. Do not treat a blog as a coverage decision.

Bottom line

Levemir (insulin detemir) is a U-100 long-acting insulin given under the skin once or twice daily. The FDA label sets type 2 starts around 10 units (or 0.1 to 0.2 units/kg) and forbids mixing, IV use, and pump use. U.S. brand supply was planned to stop after 2024. If you still use it, or if a pharmacy cannot fill it, a licensed clinician can review logs and map a safer basal option. Book a visit when you need a prescription review. Call 911 for severe lows, DKA signs, or chest pain.

Ready to talk through basal insulin? See online prescription options or browse conditions.

Educational only. Not medical advice. Coverage varies by plan. Verify benefits before booking. Klarity Health does not guarantee that any specific medication will be prescribed.