Lantus, made simple.
Lantus is insulin glargine U-100, a long acting basal insulin. It lowers glucose and must be matched to the exact concentration, device, dose, and time. The rule patients most often miss: take it once daily at the same time, and never confuse it with a mealtime insulin. A Mississippi pharmacist wrote this guide for you.
This guide is here to teach you. It is not medical advice, and it does not replace your doctor or pharmacist. Always do what your doctor tells you, and ask a pharmacist before you change how you take any medicine.
Print this guide for your fridgeYour 60 second Lantus safety checklist
- Check the label every time.Lantus is U-100 insulin glargine in a vial or SoloStar pen. Read the full insulin name and concentration before attaching a needle or drawing a dose.
- Same time every day.Inject once daily at the same time each day. It is not tied to a meal. Write your exact dose and time in your insulin schedule.
- Prime the pen and never share it.For SoloStar, do the labeled safety test with 2 units before every injection, then hold the button in and count slowly to 10 after the dose window reaches zero. Use a new needle every time. Never share a pen, syringe, or needle, even if the needle is changed.
- Rotate healthy sites.Repeated injections into lumps or thickened skin make absorption unpredictable. Show any lump, pit, or thick area to your pharmacist or clinician.
- Prepare for low blood sugar.Insulin can cause severe hypoglycemia. Carry fast carbohydrate and keep prescribed glucagon available.
- Never guess after a missed dose.Do not double. Check your glucose and call your clinician if your written plan does not cover the situation.
What Lantus is and why your doctor gave it to you
Lantus is the brand name for insulin glargine U-100. It is a long acting basal insulin, which means it works in the background between meals and overnight.
- Type 1 or type 2 diabetes in adults. Lantus is FDA approved to improve glucose control. It supplies background insulin. In type 1 diabetes, it must be used with a mealtime insulin.
- Type 1 diabetes in children. Lantus is also approved for pediatric patients with type 1 diabetes.
The simple version: Lantus provides steady background insulin over about a day. Your dose is individualized based on your diabetes type, glucose results, food, activity, illness, kidney or liver function, and other medicines.
How Lantus works
Insulin acts like a key. It helps glucose move from your blood into your muscle and fat cells, and it reduces extra glucose released by your liver.
The timing of that action depends on the insulin. A basal insulin like Lantus creates background coverage. A mealtime insulin is timed around food. They are not interchangeable.
The medicine cannot tell whether you ate, exercised, got sick, or accidentally repeated a dose. That is why glucose checks, exact timing, site rotation, and a written low glucose and missed dose plan are part of the treatment, not optional extras.
Your dose
Your Lantus dose is personal. It may change with your glucose patterns, food, activity, illness, steroid use, kidney or liver function, and other diabetes medicines. Only the clinician responsible for your care should change the prescribed dose.
Use only clear, colorless solution without particles.
With the SoloStar pen: attach a new needle, prime with the 2 unit safety test, dial the prescribed dose, inject, and keep the needle in the skin while counting slowly to 10. With the vial: use a U-100 insulin syringe.
Do not mix or dilute Lantus, use it in a pump, inject it into a vein, or withdraw it from a pen with a syringe. And never share a pen, syringe, or needle.
Timing, and what to do if you miss a dose
Inject Lantus once daily at the same time each day, under the skin of the abdomen, thigh, or upper arm, and rotate sites. It is not tied to a meal.
Lantus has no universal catch up dose in the label. That means the missed dose answer is your written plan, not a guess.
If you miss a dose:
- If a dose is late or missed, check your glucose.
- Follow your written plan, or call your diabetes team for instructions.
- Do not double, and do not take two full basal doses close together.
- If you have type 1 diabetes, check ketones when directed and seek prompt help. Lack of basal insulin can lead to ketoacidosis.
Side effects, what is normal and what is not
You may notice when you begin treatment:
- Low blood sugar: shaking, sweating, hunger, fast heartbeat, dizziness, confusion, blurred vision, or weakness. If you are awake and can swallow, follow your written plan. A common plan is 15 grams of fast carbohydrate and a recheck in 15 minutes.
- Mild redness at the injection site. Rotate sites.
- Some weight gain or fluid retention.
- Glucose changes while your body adjusts to a new insulin. Monitor more often as directed and do not stack corrections too close together.
Call your doctor or pharmacist promptly if you notice:
- Repeated glucose below your action threshold, or low readings you cannot explain.
- Glucose that stays above your call threshold despite following your correction plan.
- Moderate or large ketones, especially with type 1 diabetes.
- A wrong insulin, wrong concentration, or wrong dose error, even if you feel well.
- New injection site lumps, pits, or infection, or unpredictable glucose after changing sites.
- Rapid swelling or shortness of breath.
- Vomiting, poor intake, fever, or steroid treatment that disrupts your usual plan.
Get urgent help or call 911 if you have:
- Unconsciousness, seizure, or inability to swallow during low glucose. Give prescribed glucagon, place the person on their side, and call 911.
- Trouble breathing, face or throat swelling, or a severe allergic reaction.
- Possible diabetic ketoacidosis: vomiting, belly pain, deep or rapid breathing, fruity breath, confusion, or high glucose with significant ketones.
- A serious insulin overdose, or glucose falling fast that cannot be kept in range.
What to be careful with
Many medicines and life changes alter insulin needs. Review every change with Fairview and your diabetes team.
Other glucose lowering medicines can add to your low blood sugar risk. Beta blockers, clonidine, and some other medicines can hide the warning signs of a low, such as fast heartbeat or tremor.
Steroids, some antipsychotics, decongestants, and illness can raise glucose. ACE inhibitors, salicylates, alcohol, and some other medicines can sometimes increase low glucose risk.
Thiazolidinediones used with insulin can worsen fluid retention or heart failure. Alcohol can cause delayed low glucose, especially without food.
You do not need to memorize every interaction. Before starting, stopping, or changing another medicine or supplement, tell your pharmacist that you take Lantus.
What it costs
The cost is different for every person, because every insurance plan is different.
Here is the honest way to find your price. If you pay cash, call Fairview and we will give you a price for your situation. If you have private insurance, there may be a coupon or a savings program from the maker of the drug that helps lower your cost, and we will check if one is available for you. The best step is to let a pharmacist look at your plan. We do this for every patient.
Do not let cost make you skip doses. Call us first. There is almost always something we can do.
Availability and insurance coverage can change. Fairview will check whether an FDA approved lower cost alternative, a manufacturer savings program, an insurance exception, or another cost saving option is available for your specific prescription.
What should be checked
Lantus does its work quietly, so your numbers and your technique both need regular attention.
Your care team should follow, now and then:
- Your CGM or meter glucose patterns, including lows and highs.
- Your A1C and your individualized time in range goals.
- Your injection sites and technique.
- Kidney and liver changes that may reduce your insulin needs.
- Your weight, swelling, food intake, activity, and illness.
Your pharmacist should, now and then:
- Confirm your exact insulin, concentration, and device at every fill.
- Review your pen technique and priming steps.
- Check your glucagon supply, meter or CGM backup, ketone supplies when prescribed, and expiration dates.
- Check your medicine list for anything that changes insulin needs.
Your monitoring plan depends on why you take the medicine, your dose, your other conditions, and your other medications.
Special situations
If you become sick or cannot eat.
Do not stop basal insulin on your own. Check glucose more often, check ketones when directed, drink fluids, and call for vomiting or out of range readings. Mealtime decisions require your written sick day plan.
Travel.
Carry insulin and backup supplies in your hand luggage. Protect them from freezing and heat. Get a written time zone plan before you travel.
Pregnancy and breastfeeding.
Insulin is often used during pregnancy, but needs can change quickly. Coordinate closely with your obstetric and diabetes teams.
Kidney or liver disease.
Insulin needs may fall as function worsens, which raises low glucose risk. Monitor more often and let your clinician adjust the plan.
Driving and machinery.
Do not drive with low glucose. Check before driving when your plan directs, and carry fast carbohydrate.
Using a CGM.
Confirm with a meter when symptoms do not match the sensor or the device tells you to check. Record your insulin time and avoid stacking corrections.
Storage.
Unopened vials and SoloStar pens: refrigerate at 36°F to 46°F until the expiration date, protected from light, and never frozen. Unopened product kept below 86°F must be discarded after 28 days. An in use vial can be refrigerated or kept below 86°F and discarded after 28 days. An in use SoloStar pen stays below 86°F, is not refrigerated, is kept away from direct heat and light, and is discarded after 28 days. Remove the needle after every injection.
How Fairview helps Lantus patients
When you fill Lantus at Fairview, here is what you get. This is normal care for us, not something extra.
At your first fill:
- We confirm the medicine, strength, schedule, and treatment purpose.
- We demonstrate the SoloStar pen or vial technique, including priming and the count to 10.
- We review your low glucose plan and interactions.
- We help identify insurance barriers.
At every refill:
- We check for new medicines and ask about side effects.
- We help prevent refill gaps and review lab or appointment needs.
- We reinforce correct administration and look into cost changes.
When something changes:
- We review any new medicine and contact your prescriber when needed.
- We help you prepare medication information for surgery or travel.
- We discuss side effects and counsel an approved caregiver.
Questions people ask about Lantus
Once daily, at the same time every day.
Related guides
Have a question about your Lantus? Ask a pharmacist who knows it well.
The Lantus safety lesson: verify the exact insulin, take it once daily at the same time, and never confuse it with a mealtime insulin. Keep a written schedule, monitor your glucose, carry fast carbohydrate, and make sure someone knows how to use your glucagon. Fairview can demonstrate your exact device, review storage and travel, and help coordinate questions with your prescriber. Moving your prescription to us takes one phone call.