Lantus (insulin glargine) is a long-acting insulin. It's used to manage blood sugar levels in adults and children with Type 1 diabetes or Type 2 diabetes. Lantus (insulin glargine) is injected under the skin, typically once daily or as directed by your healthcare team. Your care team will determine your dose of Lantus (insulin glargine) based on different factors, such as your diet and blood sugar levels. Lantus (insulin glargine) comes as a vial and a prefilled insulin pen (Lantus Solostar). Some side effects of this medication include redness and swelling at the injection site, and upper respiratory tract infections.
Lantus (insulin glargine) is an insulin. Insulin is a natural hormone your body makes to control blood sugar levels. It helps your body absorb and store sugar from the bloodstream after a meal. Insulin also stops your liver from making glucose (sugar). But people with diabetes can't make insulin, don't make enough insulin, or their body doesn't respond to insulin as it should.
Lantus (insulin glargine) is a long-acting, lab-made version of insulin. It's slowly released into the body and helps your body manage blood sugar levels throughout the day. Lantus (insulin glargine) is used by people who don't make insulin or need more insulin than what their body can produce.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
behavior change similar to being drunk
blurred vision
chills
cold sweats
confusion
cool, pale skin
difficulty with thinking
dizziness or lightheadedness
drowsiness
excessive hunger
fast heartbeat
headache
nervousness
nightmares
restless sleep
seizures
shakiness
slurred speech
tingling in the hands, feet, lips, or tongue
unusual tiredness or weakness
Incidence not known
Bloating or swelling of the face, hands, lower legs, or feet
decreased urine
difficulty with swallowing
increased thirst
irregular heartbeat
muscle pain or cramps
numbness or tingling in the hands, feet, or lips
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
rapid weight gain
vomiting
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common or rare
Depression of the skin at the injection site
itching, pain, redness, or swelling at the injection site
thickening of the skin at injection site
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Can control your blood sugar levels for about 24 hours
Typically injected once daily
Approved for children and adults
Available as a vial and pre-filled pen
Given as an injection
Raises risk of dangerously low blood sugar levels
Might cause weight gain
Can't be mixed with other insulins within the same syringe
Never share Lantus (insulin glargine) pens, syringes, or needles with anyone else. Doing so puts you and others at risk of spreading germs and getting severe and potentially life-threatening infections.
It's important to check your blood sugar levels regularly to know how well Lantus (insulin glargine) is working. Keep track of your blood sugar readings so that you can share it with your diabetes care team. Your care team might adjust your dose of Lantus (insulin glargine) or other types of insulin you might be using based on trends they see.
Using Lantus (insulin glargine) can raise your risk of dangerously low blood sugar levels. It's important that you and your caregiver know how to recognize symptoms of low blood sugar level, such as sweating, shakiness, anxiety, and hunger.
When you're using Lantus (insulin glargine), make sure to always carry fast-acting sugars with you so that you can bring your blood sugar levels up when it drops too low.
Tips on how to use Lantus (insulin glargine)
Your diabetes care team will train you or your caregiver to inject Lantus (insulin glargine). Read the Instructions for Use for the pre-filled pen (Lantus Solostar) or vial and syringe (Lantus). Contact your care team if you have any questions.
Before injecting Lantus (insulin glargine), make sure the solution is clear and colorless without any particles. Otherwise, don't inject Lantus (insulin glargine) and ask your prescriber or pharmacist for a replacement.
Inject Lantus (insulin glargine) under the skin (subcutaneously) of your stomach area, thighs, or back of upper arms. Be sure to rotate injection sites to prevent hard lumps from forming in your skin. Don't inject Lantus (insulin glargine) into areas of the skin that has pits, is thickened, or is bruised and damaged.
After giving yourself the Lantus (insulin glargine) injection, throw away any needles and syringe in a sharps container or something made of heavy-duty plastic, such as an empty milk carton or laundry detergent bottle, to lower the risk of needlestick injuries. Don't throw away needles or syringes in your trash can.
Tips on storing Lantus (insulin glargine)
Unopened Lantus (insulin glargine) vials and pens can be stored in the refrigerator until the expiration date or at room temperature for up to 28 days.
Opened Lantus (insulin glargine) vials can be stored in the refrigerator or at room temperature for up to 28 days.
Opened Lantus (insulin glargine) pens should be stored at room temperature for up to 28 days, don't put them in the refrigerator.
Lantus (insulin glargine) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Never share Lantus (insulin glargine) pens, syringes, or needles with anyone else. Doing so puts you and others at risk of getting serious infections, including human immunodeficiency virus (HIV) and hepatitis B (HBV).
Changing your insulin or insulin routine, such as where you inject Lantus (insulin glargine) or switching to a Lantus (insulin glargine) biosimilar, can affect how your body responds to insulin. This can lead to either high or low blood sugar levels. In addition, injecting Lantus (insulin glargine) repeatedly into skin areas that shows signs of lipodystrophy, such as pitting or thickened skin, can also result in high blood sugar levels.
Don't make changes to your Lantus (insulin glargine) dose or routine without first checking in with your diabetes care team. Make sure to avoid injecting into skin areas that show signs of lipodystrophy. If your care team instructs you to make any changes to your insulin routine, they'll also ask you to check your blood sugar levels more often to see how the changes affect your blood sugar levels.
Risk factors: Changes in diet and exercise | Drinking alcohol | Taking other medications for diabetes together with Lantus (insulin glargine) | Liver or kidney problems | Not using Lantus (insulin glargine) as directed
Using Lantus (insulin glargine) alone or together with other medications that lower blood sugar can lead to hypoglycemia, which is dangerously low blood sugar levels. If not treated in time, it can be life-threatening.
Check your blood sugar level regularly to make sure it's within a safe range. If your diabetes care team instructs you to mix different insulins together, read the label of the insulins carefully to make sure you're using the right products. But remember, Lantus (insulin glargine) should never be mixed with other insulins in the same syringe. If you make any changes to your diet or meal patterns, other medications, or how much you exercise, let your care team know because they might need to adjust your dose of Lantus (insulin glargine).
Make sure you're familiar with symptoms of hypoglycemia, such as feeling shaky, being nervous or anxious, sweating or body chills, and excessive hunger. Keep fast-acting sugars, such as glucose tablets, with you at all times so you can treat an episode of hypoglycemia. If your blood sugar levels don't improve even after you take fast-acting sugars, get medical help right away.
Risk factors: Taking other medications with Lantus (insulin glargine) that lower potassium
Lantus (insulin glargine) can cause low potassium levels in your blood, which can be dangerous. You're at higher risk if you're already taking medications that can lower potassium levels, such as loop diuretics. Because people with low blood potassium levels typically don't experience any symptoms, your care team might order blood tests to check your potassium levels regularly. And if needed, they'll prescribe you medications to bring your potassium level within a safe range. Get medical help right away if you notice symptoms of low potassium levels such as weakness, muscle cramps or twitches, and constipation.
Risk factors: Taking glitazones together with Lantus (insulin glargine) | Heart failure
Taking Lantus (insulin glargine) with glitazones (also known as thiazolidinediones), like Actos (pioglitazone), can cause your body to hold onto fluid. This can be especially dangerous if you have heart failure because additional fluid can worsen your condition and cause symptoms such as difficulty breathing, swelling, and tiredness.
Make sure to tell your diabetes care team if you have heart failure or if you're taking a glitazone before starting Lantus (insulin glargine).
Rarely, Lantus (insulin glargine) can cause a serious, life-threatening reaction (e.g., anaphylaxis). If you experience swelling in your lips, face, or tongue, rash, or trouble breathing, get medical help right away.
Your diabetes care team will work with you to determine your dose of Lantus (insulin glargine). The dose of Lantus (insulin glargine) will be different for each person. It depends on different factors, such as whether you have type 1 or type 2 diabetes and how well your body responds to insulin. You might need to use a fast-acting insulin along with Lantus.
Type 1 diabetes: Your care team will help you calculate your total daily insulin (TDI) requirement. The typical starting dose is about 30% of your TDI requirement, injected under the skin once daily.
Type 2 diabetes: Your care team will help you calculate your starting dose based on your body weight. The typical starting dose is 0.2 units/kg (up to 10 units) injected under the skin once daily.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Low blood sugar (hypoglycemia)
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American Diabetes Association. (2012). Hypoglycemia? Low blood glucose? Low blood sugar? Clinical Diabetes.
Lantus. (n.d.). Using Lantus? Learn how to inject insulin.
Sanofi-aventis U.S. LLC. (2022). How to use your Lantus SoloStar pen.
Sanofi-aventis U.S. LLC. (2023). LANTUS- insulin glargine injection, solution; LANTUS SOLOSTAR- insulin glargine injection, solution [package insert]. DailyMed.
Sharabi, K., et al. (2015). Molecular Pathophysiology of Hepatic Glucose Production. Molecular Aspects of Medicine.
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