What is Semglee: Uses, Warnings & Interactions

Updated May 14, 2025  •  Published Dec 31, 2020

Semglee is a brand-name long-acting insulin. Its active ingredient is insulin glargine, which keeps insulin levels steady and blood sugar low throughout the day in people with diabetes mellitus. Patients or their caregivers inject the medicine at home using a prefilled injection pen or vial with a needle and syringe. Doses are injected once daily at the same time every day.

Semglee overview

BRAND NAMES:

  • Semglee

Generic Names:

  • Insulin glargine

Uses:

  • Treats diabetes

Therapeutic Classes:

  • Antidiabetic, long-acting human insulin

Forms:

  • Injectable

How it’s taken:

  • By injection

What is Semglee used for?

Semglee is a long-acting basal insulin FDA-approved for use in adults and children 6 years of age and older with Type 1 diabetes and adults with Type 2 diabetes. Semglee is not appropriate for managing blood sugar spikes after a meal or for managing diabetic ketoacidosis.

What form(s) does Semglee come in

  • Injection pen 

    • 3 mL of 100 unit/mL

  • Vial 

    • 10 mL of 100 unit/mL

What are common Semglee doses?

  • For Type 1 diabetes:

    • In adults: Doses will vary; injections are administered once daily at the same time every day

    • In children 1 year of age and older: Doses will vary; injections are administered once daily at the same time every day

  • For Type 2 diabetes: Doses will vary but start at 0.2 units/kg up to a maximum of 10 units daily; injections are administered once daily at the same time every day

Common Semglee prescriptions

  • Semglee
    3ml of 100unit/ml pen

  • Semglee
    10ml of 100unit/ml vial

How to take Semglee

  • Follow all the directions given by the healthcare team.

  • Please read the Patient Information sheet included with the medicine.

  • A healthcare provider will demonstrate how to administer an injection and where on the body to make an injection.

  • Use a different body area for each injection.

  • Read and follow the illustrated Instructions for Use that come with the vial or injection pen.

  • Inject only one dose daily.

  • Doses can be injected at any time of day but must be taken at the same time every day.

  • A caregiver should administer SoloStar injections for people who are blind or have vision problems.

  • Do not share syringes, needles, or injection pens with other people.

  • Do not inject into skin that is damaged, bruised, thick, lumpy, scaly, hard, or scarred.

  • A caregiver should administer injections for people who are blind or have vision problems.

  • Do not use Semglee in an insulin pump.

  • How to prepare for an injection:

    • Wash your hands.

    • Check the insulin type, concentration, expiration date, and appearance of the medicine. 

    • The medicine should appear clear and colorless. Do not use it if it is discolored, cloudy, or contains particles.

  • How to administer injections using a needle and syringe:

    • Use a new syringe for each injection.

    • Use only syringes designed for U-100 insulin injections. 

    • Do not mix Semglee with any other insulin.

    • Administer injections only under the skin (subcutaneously), never into a vein or a muscle.

    • Wipe the skin with an alcohol swab and let dry.

    • Draw the medicine into the syringe as instructed.

    • Pinch the skin.

    • Insert the needle into the skin as instructed by the healthcare team. 

    • Slowly push down the plunger until all the medicine is injected.

    • Keep the needle in the skin for at least ten seconds.

    • Pull the needle out of the skin.

    • Press gently on the injection site for a few seconds.

    • Do not recap the needle.

    • Dispose of the needle and syringe in a sharps container.

    • Dispose of the empty vial in a sharps container.

    • Store the unopened vials in the refrigerator. Do not freeze.

    • Protect the medicine from heat and light.

    • Throw away unopened vials after 28 days.

  • Using an injection pen:

    • Attach a needle. Always use a new needle for each injection. 

    • Do a safety test before each injection. Follow the step-by-step directions in the Instructions for Use. 

    • If the safety test fails, attach a new needle and perform the safety test a second time.

    • If the safety test fails a second time, do not use the pen. Start with a new pen.

    • If the safety test succeeds, select the dose on the dose selector. 

    • If there’s not enough medicine in the pen to give a complete dose, use the pen to inject what’s left in the pen. Use a new pen to inject the remaining part of the dose.

    • Wipe the skin with an alcohol swab and let dry.

    • Insert the needle into the skin. 

    • Slowly and gently press the injection button straight down with your thumb.

    • Press and hold the injection button until the dose counter reaches “0.” 

    • Slowly count to “10” with the needle in the skin and the injection button pressed down.

    • Release the injection button and pull the needle out of the skin.

    • Carefully replace the outer needle cap.

    • Remove the needle from the pen and dispose of it in a sharps container. 

    • Replace the pen cap.

    • Do not put the pen back in the refrigerator.

    • Store unused pens in the refrigerator. Do not freeze.

    • Store used pens with the pen cap on at room temperature, protected from heat and light.

    • Never keep the needle attached to a pen when not in use.

What to do if you miss a dose of Semglee

  • The prescriber or healthcare team should provide you with a plan for managing missed doses. Follow that plan.

  • If not, ask the prescriber what to do in case of a missed dose. Follow the prescriber’s instructions.

  • The prescriber or healthcare team may advise that a missed dose: 

    • Be taken within a specified number of hours after its scheduled time

    • Be replaced by a remedial dose (lower dose) to be taken within a specific number of hours after the dose is missed

    • Be skipped entirely 

  • If you don’t have clear instructions from the prescriber, call or visit a doctor or urgent care.

  • If a dose is skipped, remember to test blood sugar levels throughout the day and treat high blood sugar with fast-acting insulin.

  • Never take two doses of insulin to make up for a missed dose.

Semglee contraindications

  • This medicine is not right for everyone. 

  • Do not use it if you have had an allergic reaction to insulin glargine.

  • Do not use Semglee during episodes of low blood sugar (hypoglycemia).

Semglee warnings

  • Diabetic patients require regular doctor’s visits, blood tests, and dose adjustments when taking insulin. Keep all appointments.

  • Ensure other doctors and healthcare providers know you’re taking insulin. 

  • Tell the prescriber if you are pregnant, planning to become pregnant, or breastfeeding.

  • Tell the prescriber about all your medical conditions, particularly liver or kidney problems.

  • Blood sugar levels are affected by diet and lifestyle, so any significant changes may require insulin doses to change. Always tell the prescriber about changes in:

    • Diet

    • Physical activity

    • Exercise

    • Stress

    • Health (illness, injury, or surgery)

    • Medications

    • Changes in stress

  • The most common side effect of insulin treatment is low blood sugar (hypoglycemia). Know the symptoms of hypoglycemia and follow the doctor’s instructions when you experience them.

  • The ever-present risk of hypoglycemia increases the risk of accidents and injuries. Do not drive or do any other risky activity until you feel stabilized on insulin treatment. 

  • Low potassium is another possible side effect. Know the clinical signs of low potassium and call a healthcare provider or get medical help if they occur.

  • Do not share syringes, needles, insulin, or the Semglee injection pen with other people.

Semglee interactions

  • Make sure the prescriber knows about all the prescription drugs, over-the-counter medications, and supplements you take, even if they’re only used occasionally.

  • Always inform your healthcare team when you start or stop a new drug or supplement.

  • Insulin glargine has a long list of potentially serious drug interactions. That’s because many drugs affect blood sugar levels or cause other problems when taken with long-acting insulins. Drugs the doctor must know about include:

  • Do not drink alcohol or take medications containing alcohol when taking insulin.

Semglee side effects

Serious Side Effects

Talk to the prescriber if you notice any signs or symptoms of a possible serious side effect of Semglee, including:

  • Dizziness, lightheadedness, sweating, confusion, headache, blurred vision, slurred speech, shaking, racing heartbeats, mood changes, anxiety, irritability, hunger

  • Muscle twitches, muscle weakness, fatigue, heart palpitations, numbness or tingling

  • Shortness of breath, sudden weight gain, swelling of the ankles or feet

  • Chest pain, trouble breathing, fatigue

  • Allergic reaction: Whole body rash, difficulty breathing, shortness of breath, fast heart rate, sweating

Less Serious Side Effects

  • Low blood sugar

  • Weight gain

  • Injection site reactions such as redness or swelling

  • Injection site skin thickening or pits

Sources: