6 Insulin Side Effects You Should Know About
General insulin use may cause a few common side effects. Typical insulin side effects include irritation at the injection site, weight gain, and headaches.
insulin aspart
Used for Diabetes Type 1, Diabetes Type 2
Used for Diabetes Type 1, Diabetes Type 2
NovoLog (insulin aspart) is a fast-acting insulin for adults and children with diabetes. It lowers your blood sugar levels by moving the sugar into your body so it can be used for energy. NovoLog (insulin aspart) is available as vials and ready-to-use prefilled pens. It's typically injected under the skin at mealtimes, but it can also be given as an infusion into the veins by a healthcare provider for people in the hospital. Side effects include headache and low blood sugar (hypoglycemia).
What is NovoLog (insulin aspart)?
What is NovoLog (insulin aspart) used for?
- Type 1 diabetes in adults and children
- Type 2 diabetes in adults
How NovoLog (insulin aspart) works
NovoLog (insulin aspart) is an insulin, which is a natural hormone your body normally makes to lower glucose (sugar) levels in the blood. Insulin helps your body absorb sugar from your bloodstream after you eat a meal to use for energy. Insulin also stops your liver from making sugar.
When does NovoLog (insulin aspart) start working?Time passed since treatment started:
Drug facts
| Common Brands | NovoLog, NovoLog FlexPen, NovoPen Echo, NovoLog FlexTouch |
|---|---|
| Drug Class | Insulin |
| Controlled Substance Classification | Not a controlled medication |
| Generic Status | Lower-cost generic available |
| Availability | Prescription only |
More on NovoLog (insulin aspart) essentials
Side effects of NovoLog (insulin aspart)
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
Type 1 diabetes:
- Severely low blood sugar (17%)
- Headache (12%)
- Accidental injury (11%)
- Nausea (7%)
- Diarrhea (5%)
Type 2 diabetes:
- Muscles slow to react (11%)
- Severely low blood sugar (10%)
- Fungal nail infection (10%)
- Impairment of your senses (9%)
- Urinary tract infection (8%)
- Sinus infection (5%)
- Chest pain (5%)
- Stomach pain (5%)
- Headache (5%)
- Skin problems (5%)
Less Common Side Effects
- Weight gain
- Swelling
- Reactions at the injection site (e.g., redness, swelling, itching)
- Thickened or pitted area of skin at injection site (under-the-skin injections only)
Note: Side effects listed were reported by adults. Side effects might differ for children.
NovoLog (insulin aspart) serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Severely low blood sugar: dizziness, shakiness, feeling confused, feeling irritable or anxious, feeling faint, sweating, extreme hunger, not able to think clearly
- Ketoacidosis (high ketone levels in the blood): nausea, vomiting, stomach pain, tiredness, thirsty, dry mouth, fruity breath, trouble breathing
- Severely low potassium levels: weakness, muscle cramps or twitches, constipation, abnormal heartbeat, tiredness, trouble breathing
- Severe allergic reactions: rash; hives; swelling of face, tongue, and throat; trouble breathing
When do NovoLog (insulin aspart) possible side effects begin and end?
Time passed since treatment started:
M
H
D
W
M
Injection site reactions
Headache
Weight gain
Risk of low blood sugar levels
Seek immediate medical care if you experience this side effect.
If a line continues to the right, you'll likely keep experiencing this side effect once it starts.
More on NovoLog (insulin aspart) side effects
The following NovoLog (insulin aspart) side effects have also been reported
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
- Low blood sugar (hypoglycemia)—tremors or shaking, anxiety, sweating, cold or clammy skin, confusion, dizziness, rapid heartbeat
- Low potassium level—muscle pain or cramps, unusual weakness or fatigue, fast or irregular heartbeat, constipation
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
- Lipodystrophy—hardening or scarring of tissue at injection site
- Pain, redness, or irritation at injection site
- Weight gain
Get your GoodRx coupon
$24.91
GoodRx discount
$24.88
Pros and cons of NovoLog (insulin aspart)
Pros
- Starts to work within 10 minutes to lower blood sugar levels
- Dose can be easily adjusted to make treatment tailored to your specific needs
- Can use if you have liver or kidney problems
- Available as a prefilled pen for easier and convenient use
Cons
- Given multiple times per day (before each meal)
- Must give as an injection
- Might be hard for some people to inject properly
- Risk of low blood sugar and weight gain
Pharmacist tips for NovoLog (insulin aspart)
- Make sure you know how to use NovoLog (insulin aspart) properly and safely to avoid accidentally hurting yourself or wasting the medication. Carefully review the instructions for use, and contact your provider or pharmacist for specific directions and for any questions you have.
- If you're prescribed NovoLog (insulin aspart) with other types of insulin, ask your provider or pharmacist about the best way to take your insulins. You might need to take each insulin medication at different times of the day. Don't mix other types of insulins in the same syringe as NovoLog (insulin aspart), unless your provider told you to.
- Don't use NovoLog (insulin aspart) if you plan to skip a meal, unless your provider specifically told you to do so. Using NovoLog (insulin aspart) without a meal raises your risk for hypoglycemia (dangerously low blood sugar).
- Ask your provider about when you should check your blood sugar during the day as you use NovoLog (insulin aspart). Make sure to keep a log of your blood sugar readings and show it to your provider at your office visits. This helps you and your provider keep track of how well you're responding to NovoLog (insulin aspart) and whether you need dose adjustments.
- It's important that you and your loved ones know how to recognize and treat low blood sugar. Common symptoms include shakiness, anxiety, and hunger. Always keep fast-acting sugar, such as glucose tablets, with you at all times so you can take it if your blood sugar level drops too low. Follow the "15-15 rule" to treat low blood sugar levels (below 70 mg/dL).
Tips on how to store NovoLog (insulin aspart):
- Store unopened vials and pens in the refrigerator until the expiration date. You can also keep them at room temperature for up to 28 days.
- Store opened vials in the refrigerator or at room temperature for up to 28 days. Keep opened pens at room temperature for up to 28 days; don't put them in the refrigerator.
Tips on how to use NovoLog (insulin aspart):
- Always use a new needle for each injection to help prevent infections and blocked needles. Don't reuse or share your injection supplies with other people to avoid spreading infections.
- Before each time you use NovoLog (insulin aspart), double check that you're using the correct insulin product and that your dose (number of units) that you've prepared is correct. This is important to prevent dosing mistakes that could lead to dangerously low blood sugars if you accidentally inject too much insulin.
- For NovoLog pens (FlexPen and FlexTouch): Prime the pen each time before you dial your dose and inject. This makes sure there aren't any air bubbles in your dose. Turn the dose selector to 2 units, hold the pen with the needle pointing up, gently tap it so any air bubbles go to the top, and push the dose button until the dose counter says "0." Repeat if you don't see any insulin at the needle tip.
- For under-the-skin injections: Inject NovoLog (insulin aspart) within 5 to 10 minutes before a meal. Inject the medication under the skin in the stomach area, buttocks, upper legs (thighs), or upper arms. Pick a different injection site each time to prevent hard lumps from forming in the skin or pitted or thickened skin.
- For continuous infusion pumps: Infuse NovoLog (insulin aspart) into an area of the body recommended by the manufacturer of the pump. Rotate injection sites to prevent skin irritation. Change the medication in the pump at least once per week or according to the user manual, whichever is shorter. Also replace any medication in the pump that's been exposed to temperatures above 98.6°F.
- After injecting NovoLog (insulin aspart), throw the needle or syringe away in a sharps container or something made of heavy-duty plastic (e.g., empty milk carton, laundry detergent bottle). This helps lower the risk of needle-stick injuries. Don't throw away needles or syringes in your trash can. Visit the FDA's website for guidance on how to safely throw away your sharps container in your specific state.
More on NovoLog (insulin aspart) tips
Risks and warnings for NovoLog (insulin aspart)
NovoLog (insulin aspart) 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.
Spread of infections from sharing injection supplies
Never share NovoLog (insulin aspart) pens, syringes, needles, or cartridges with anyone else. Sharing NovoLog (insulin aspart) and injection supplies with someone can raise the risk of spreading very dangerous infections to other people (including yourself).
Low blood sugar (hypoglycemia)
- Risk factors: Changes in diet and exercise | Switching to NovoLog (insulin aspart) from a different type of insulin | Drinking alcohol | Taking other medications for diabetes together with NovoLog (insulin aspart) | Liver or kidney problems
Using NovoLog (insulin aspart) alone or together with other blood sugar medications can cause your blood sugar levels to drop too low, which can be life-threatening. Always check the medication labels of all your diabetes medications to make sure you're taking the right one, especially if you're injecting more than one type of insulin.
Make sure you and your loved ones know how to recognize symptoms of low blood sugar, such as feeling shaky; being nervous, anxious, or confused; or feeling very hungry. Check your blood sugar if you have any of these symptoms.
It's important to know how to treat low blood sugar. Carry some form of fast-acting sugar (e.g., glucose tablets, hard candy, fruit juice) with you at all times while you're taking this medication. You can use these to raise your blood sugar quickly if it becomes too low.
Low blood potassium levels
- Risk factors: Taking other medications that lower potassium levels
NovoLog (insulin aspart) can lower the levels of potassium in your blood, which can sometimes be dangerous. You're at risk if you're already taking medications that lower your potassium, like certain diuretics (water pills). Your provider will check your potassium levels regularly and might give you medications to keep your potassium in the normal range. Tell your provider if you have symptoms of low potassium, such as weakness, muscle cramps or twitches, nausea, vomiting, or abnormal heartbeats.
Swelling from fluid buildup and risk of heart failure when taken with certain blood sugar medications
- Risk factors: Taking glitazones together with NovoLog (insulin aspart) | History of heart failure
Taking NovoLog (insulin aspart) with medications called glitazones (also known as thiazolidinediones), like pioglitazone (Actos), can cause your body to hold onto fluid. This can worsen or lead to heart failure. Let your provider know if you've noticed sudden weight gain or if you have symptoms of heart failure, such as trouble breathing, tiredness, or headache. Your provider might need to make changes to your blood sugar medications.
Dangerously high blood sugar levels or buildup of ketones (for people who use insulin pump)
- Risk factors: Insulin pump not working properly
If you're using an insulin pump to inject NovoLog (insulin aspart), check that your pump is working properly and that you know how to use it correctly. When the pump isn't work properly, you're at risk of having extremely high blood sugar levels or a serious complication of diabetes called ketoacidosis. Call your provider right away if you can't fix your pump quickly. Your provider might recommend that you inject NovoLog (insulin aspart) in other ways in the meantime. Tell your provider as soon as possible if you have symptoms of ketoacidosis, such as tiredness, fruity-smelling breath, or vomiting.
NovoLog (insulin aspart) dosage
The average cost for 1 vial of 10ml of 100 units of NovoLog (insulin aspart) is $80.60 with a free GoodRx coupon. This is 25.02% off the average retail price of $107.49.
Typical dosage for NovoLog (insulin aspart)
Your healthcare provider will work with you to find the dose that works best for you. Your dose depends on many things, such as whether you have Type 1 or Type 2 diabetes, your blood sugar levels and how they change with insulin, and how you're injecting the medication (under the skin, into the vein, using an insulin pump).
- For injections under the skin: Inject NovoLog (insulin aspart) under the skin in the stomach, thigh, upper arm, or buttocks area within 5 to 10 minutes before a meal.
- For injections through the vein: NovoLog (insulin aspart) can be given as an injection or slow infusion into the vein by a healthcare provider.
- For continuous insulin pumps: Use the insulin pump according to your provider's instructions. Follow the directions from your insulin pump manufacturer to set up and use the pump.
How much does NovoLog (insulin aspart) cost?
To access savings, use a GoodRx coupon and pay just a fraction of the retail price.
NovoLog (insulin aspart) contraindications
Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because NovoLog (insulin aspart) will not be safe for you to take.
- When you have low blood sugar (hypoglycemia)
What are alternatives to NovoLog (insulin aspart)?
There are a number of medications that your doctor can prescribe in place of NovoLog (insulin aspart). Compare a few possible alternatives below.
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