Drug Detail:Lantus (Insulin glargine [ in-su-lin-glar-gine ])
Drug Class: Insulin
1. How it works
- Lantus is a brand name for a type of long-acting insulin called insulin glargine.
- Insulin glargine is a biosynthetic human insulin analog of rDNA origin that has been made using genetic engineering technology. Although it resembles human insulin in most of its structure, the amino acid arginine in position A21 has been replaced by glycine and two arginines have been added to the C-terminus of the B-chain.
- Lantus was formulated to have a low insulin solubility at neutral pH which means it forms microprecipitates when injected under the skin (subcutaneously), which allows the insulin to be released slowly from the injection site.
- The primary activity of insulin, which includes Lantus, is to allow cells throughout the body to uptake glucose (sugar) and convert it into a form that can be used by these cells for energy.
2. Upsides
- May be used for the treatment of type 1 diabetes in adults and children over the age of six who require long-acting insulin for their diabetes control.
- Lantus is a long-acting insulin that lasts 24 to 36 hours depending on its concentration. Only needs to be given once a day.
- May be used to control blood sugar levels in adults with type 2 diabetes who require long-acting insulin when other medications are no longer effective at improving blood sugar levels.
- Available in a fixed combination with lixisenatide (a GLP-1 receptor agonist).
- Lantus is available as Lantus Solostar U-100 prefilled pen which is for single patient-use. This 3mL pen contains 300 units of insulin. Units can be increased by 1 unit at a time by moving the dial on the pen. The maximum dosage for each use is 80 units. Lantus is also available in a 10mL vial. The vial contains 1000 units of Lantus.
- Lantus does not pass into breast milk and will not affect a nursing infant.
- Generic insulin glargine is available.
3. Downsides
If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:
- Low blood sugar levels (hypoglycemia) are the most common side effect of Lantus. The risk of hypoglycemia increases with tighter blood sugar controls, changes in meal patterns, certain coadministered medications, and changes in physical activity levels. People with liver or kidney disease may be at a higher risk of hypoglycemia.
- All insulins can cause potassium levels to go low (this is called hypokalemia). Insulin may also cause sodium retention, weight gain, fluid retention and swelling, itching, redness, or lumps around the injection site. There is a risk of infection if a Lantus pen is shared.
- The dosage of Lantus needs to be reduced for liver or kidney disease. Blood glucose levels should be carefully monitored in people with these conditions.
- Seniors may be more susceptible to the side effects of long-acting insulins, such as insulin glargine. The dosage of Lantus in elderly people should be conservative.
- Lantus must be given by subcutaneous (under the skin) injection. It should not be given by IV or IM injection or in an infusion pump.
- Lantus is not suitable for the treatment of diabetic ketoacidosis. Short-acting insulins should be used to treat this condition.
- Seniors may have more difficulty using Lantus preparations due to poor vision or dexterity problems, making it difficult to dial the correct dosage or inject insulin into their skin.
- Research has not shown a clear association between insulin use during pregnancy and adverse developmental outcomes in the fetus. There is limited data on the presence of Lantus in breast milk and its effects on a nursing infant.
Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects
4. Tips
- Tell your doctor if you have ever had an allergic reaction to any type of insulin before you start using Lantus.
- Children are especially sensitive to the effects of insulin, particularly around puberty.
- There are so many different types of insulin that medication errors are common. Always check the label on your insulin to make sure it is the brand you have been prescribed and it is the correct strength. Talk to your doctor or pharmacist if you are unsure. Always make sure you have drawn up the correct dose of insulin for you.
- The dosage of Lantus needs to be individualized. This may take time, so ensure you monitor your blood sugars regularly when titrating the dosage of Lantus, and tell your doctor the results.
- Never share your Lantus pen with other people. Store your pens as recommended on the label.
- Inject your insulin exactly as directed by your doctor. Take all other medications as prescribed.
- Your insulin requirements may change if you become unwell, develop an infection, or have other medical conditions. Surgery, injury, mental stress, diet, and how much exercise you do can also affect how much insulin you need. Puberty, pregnancy, and menopause can also affect insulin requirements. Conditions that delay food absorption or stomach emptying can slow down the time it takes to break down and absorb food which can change how much insulin you need.
- Be alert for symptoms of hypoglycemia which may include a headache, sweating, trembling, anxiety, confusion, irritability, rapid breathing, or a fast heartbeat. People with hypoglycemia may also faint and severe hypoglycemia that is left untreated may be fatal. Tell your family, friends, and caregivers to give you some fast-acting sugar (such as some jellybeans, fruit juice, or honey) if they notice you have symptoms of hypoglycemia, and then follow it up with a more substantial meal or glucagon injection if you are unconscious.
- Insulin is easily broken down by extreme temperatures, which means you need to be careful if you live in a part of the U.S. that gets very hot in summer, or very cold in winter.
- Opened and in-use cartridges and vials may be kept at room temperature (59 to 77 degrees Fahrenheit [15-25 degrees Celcius]) for up to 28 days.
- If you are going out in the sun, always use an insulated bag protected by a cool pack to ensure your insulin doesn't heat up; but avoid freezing it. During cold weather, keep your insulin supplies close to your skin so your body heat keeps them at a more even temperature. Discard any insulin that you think may have inadvertently got too hot or too cold. The expiry date on insulin applies to unopened, refrigerated insulin.
5. Response and effectiveness
- Starts to work within 70 minutes after injection
- Has no pronounced peak but full blood sugar-lowering effects can take one to three hours to develop after administration
- Keeps working for up to 24 to 36 hours depending on its concentration.
6. Interactions
Medicines that interact with Lantus may either decrease its effect, affect how long it works, increase side effects, or have less of an effect when taken with Lantus. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.
Common medications that may interact with Lantus include:
- antibiotics, such as doxycycline and minocycline
- antidepressants such as SSRIs (eg, fluoxetine, sertraline), monoamine oxidase inhibitors (MAOI) such as selegiline, isocarboxazid, and phenelzine
- antiepileptics, such as fosphenytoin and phenytoin
- antipsychotics, such as aripiprazole, chlorpromazine
- antivirals such as amprenavir, atazanavir, and fosamprenavir
- aspirin
- beta-blockers, such as acebutolol, atenolol, or timolol
- cyclosporine
- diuretics, such as furosemide, chlorthalidone, or hydrochlorothiazide
- fluoroquinolone antibiotics, such as ciprofloxacin or norfloxacin
- gemfibrozil
- heart medications such as captopril, candesartan, or clonidine
- hormones, such as estradiol, estrone, and norethindrone
- lithium
- niacin
- pentamidine
- salmeterol
- steroids, such as cortisone, dexamethasone, fludrocortisone, or prednisone
- sucralfate
- tacrolimus or pimecrolimus
- topiramate
- turmeric
- aloe vera
- other insulins
- other medications that affect blood sugar levels or are used for diabetes, such as chlorpropamide, glimepiride, or glipizide.
Alcohol may also interact with Lantus by blocking the production of glucose by the liver, causing hypoglycemia.
Note that this list is not all-inclusive and includes only common medications that may interact with Lantus. You should refer to the prescribing information for Lantus for a complete list of interactions.