If you’re looking at treatment options for diabetes, your doctor might suggest Humulin R U-500 (insulin human).

Humulin R U-500 is a prescription medication that’s used to manage blood sugar levels in certain adults and children. Specifically, it’s used in people with type 1 or type 2 diabetes who need more than 200 units of insulin per day. For details about diabetes, see the “What is diabetes?” section below.

Humulin R U-500 belongs to a group of biologic drugs called insulins. The active ingredient in Humulin R U-500 is recombinant human insulin.

The drug comes as a clear liquid that you’ll inject under your skin. It’s available in two forms: vials and prefilled pens called KwikPens.

This article gives details on Humulin R U-500 and its use in managing diabetes. You can alsosee this in-depth article for more information about Humulin R U-500.

This section describes how you’ll typically use Humulin R U-500 for diabetes. Be sure to follow your doctor’s instructions on how to take this medication.

Humulin R U-500 comes as a liquid that’s available in:

What is the typical dosage for Humulin R U-500?

There’s no standard or recommended dosage of Humulin R U-500. The dosing for this type of insulin is customized for you by your doctor.

Your doctor will determine your exact dosage of Humulin R U-500 based on several factors. These include:

  • your average blood sugar levels
  • your risk factors for hypoglycemia (low blood sugar level)
  • the total daily insulin dose you’ve typically needed in the past
  • other medications you take, including other types of insulin
  • other medical conditions you have

Your doctor may adjust your dosage over time as your needs change. For example, losing weight can lower your blood sugar levels. This can reduce your need for Humulin R U-500.

You’ll likely inject Humulin R U-500 at least two or three times per day. You’ll inject each dose 30 minutes before eating a meal.

It’s important not to skip eating a meal after you take a dose of Humulin R U-500. If you take a dose but don’t eat a meal 30 minutes later, your blood sugar levels may become very low. This can be life threatening.

How do you use Humulin R U-500?

You’ll use Humulin R U-500 by injecting it under your skin. Your doctor or pharmacist will show you how to give yourself injections with an insulin syringe or the KwikPen. Humulin R U-500 can be injected into your thighs, belly, upper arms, or buttocks.

Be sure to inject the drug into a different area for each dose. For example, you can inject your medication into your belly, but make sure to use a different part of your belly for each dose. Using the same spot each time can cause side effects at your injection site, such as hard lumps.

Using a KwikPen

The Humulin R U-500 KwikPen is a pen that’s filled with clear liquid. You’ll attach a new pen needle before each injection.

On the KwikPen, each click of the knob measures out five units of the insulin. The dose window shows the total number of units that you’ll inject.

Instructions for how to use the Humulin R U-500 KwikPen are included in the product labeling. A how-to-use video is also available. If you have questions about using the KwikPen, talk with your doctor or pharmacist.

Using a vial and syringe

Humulin R U-500 also comes in a vial. Each vial contains 20 milliliters of clear liquid. With the vial, you’ll use an insulin syringe to inject your dose.

It’s very important to check that your insulin syringes have a green cap and are labeled “U-500.” With U-500 insulin syringes, each line on the syringe measures 5 units of insulin.

Using other types of syringes with Humulin R U-500 raises your risk of dosing mix-ups. This can cause serious side effects, such as very low blood sugar levels.

Instructions for how to use Humulin R U-500 vials and syringes are included in the product labeling. A how-to-use video is also available. And your doctor or pharmacist can help if you have questions.

How often should I use Humulin R U-500?

You’ll likely inject Humulin R U-500 at least two or three times per day. You’ll inject each dose 30 minutes before eating a meal.

Be sure to follow your doctor’s dosage instructions, which may not be the same for each dose of Humulin R U-500. For example, you may take 125 units of the drug 30 minutes before breakfast and 85 units 30 minutes before dinner.

Using Humulin R U-500 (insulin human) for diabetes (its only approved use) may cause side effects in some people. These side effects can be mild or serious.

The lists below include some of the main side effects that have been reported in people using Humulin R U-500. For information about other possible side effects of the drug, talk with your doctor or pharmacist.

You can also learn more from this article on Humulin R or from the Humulin R U-500 prescribing information.

What are Humulin R U-500’s mild side effects?

Humulin R U-500 causes mild side effects in some people, such as:

  • hypoglycemia (low blood sugar level)
  • weight gain
  • itching
  • rash
  • fluid buildup in your arms, legs, or feet
  • side effects at your injection sites, such as:
    • bruising or bleeding
    • swelling or warmth
    • skin discoloration
    • thick, hardened skin or lumps

In many cases, mild side effects from the drug can be temporary. Some side effects may be easy to manage, too. But if side effects last longer, or if they bother you or become severe, talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Humulin R U-500, visit MedWatch.

What are Humulin R U-500’s serious side effects?

Less commonly, Humulin R U-500 may cause serious side effects in some people. These can include:

Call your doctor right away if you have any serious side effects while using Humulin R U-500. If the side effects seem life threatening or if you think you’re having a medical emergency, call 911 or your local emergency number immediately.

Studies have shown that Humulin R U-500 is effective for managing blood sugar levels in certain people with diabetes. (Specifically, it’s used in adults and children who need more than 200 units of insulin per day.)

Guidelines from the American Diabetes Association recommend human insulin (the active drug in Humulin R U-500) for treating type 1 and type 2 diabetes.

With Humulin R U-500, you may be able to inject yourself fewer times per day. This is compared with other insulin regimens that use separate shorter-acting insulins and longer-acting insulins.

To find out if Humulin R U-500 treatment may be right for you, talk with your doctor.

Get answers to frequently asked questions about Humulin R U-500.

Is Humulin R U-500 a long-acting insulin?

Yes, Humulin R U-500 can be used as a long-acting insulin and also as a mealtime insulin. Humulin R U-500 is different from some other long-acting insulins in that you’ll need to use at least two or three injections per day, though.

Humulin R U-500* acts as both a long-acting and mealtime insulin because it’s a highly concentrated form of insulin.

If your doctor prescribes at least two or three daily injections of Humulin R U-500, you shouldn’t need to use any other types of insulin. If you have questions about how to use this type of insulin, talk with your doctor or pharmacist.

* Humulin R is also available in a strength called Humulin R U-100. This is a short-acting form of insulin that only helps manage mealtime insulin needs.

Can I convert Humulin R U-500 insulin to U-100 strength?

No, you should not switch from the U-500 strength to the U-100 strength of Humulin R unless your doctor prescribes this for you. To prepare each injection of Humulin U-500, follow the directions on the prescription label on the container.

If your doctor recommends switching from one insulin type to another (for example, from long-acting or short-acting insulin), be sure to follow their instructions carefully.

You should not try to convert, mix, or dilute (decrease the strength of) Humulin R U-500 insulin. This is very important because mix-ups with Humulin R U-500 dosing may lead to serious side effects. These can include severe hypoglycemia (very low blood sugar level), which can be life threatening.

If you have questions about your dosage of Humulin R U-500, talk with your doctor or pharmacist.

The price of Humulin R U-500 depends on several factors. These can include your treatment plan, your insurance plan, the pharmacy you use, and your location. For estimates of how much Humulin R U-500 costs, visit GoodRx.com.

Also, keep in mind that you’ll need to purchase insulin syringes or pen needles to inject insulin. Your doctor may provide a separate prescription for syringes or needles. Costs for these supplies can vary.

If you’re interested in patient financial assistance that helps cover the cost of this drug, talk with your doctor or pharmacist. You may also be eligible for a savings card offered by the manufacturer. For information, visit the manufacturer’s website.

Humulin R U-500 is a brand-name biologic drug. It’s not available as a generic or biosimilar form. (Brand-name drugs usually cost more than generics.) To learn about other medications with available generics, talk with your doctor or pharmacist.

Diabetes is a condition that affects your metabolism. It causes high blood sugar due to your body having problems making or using insulin.

Insulin is a hormone that moves sugar from your blood into your cells. Once inside your cells, sugar can be stored or used for energy.

With diabetes, your body either doesn’t make enough insulin or can’t use it properly. This leads to high blood sugar levels, which can cause symptoms of diabetes. If untreated, diabetes can cause nerve and organ damage.

Humulin R U-500 is used to manage blood sugar levels in certain people with type 1 or type 2 diabetes. With type 1 diabetes, your pancreas doesn’t produce enough insulin. And with type 2 diabetes, your body can’t properly use the insulin that your pancreas produces.

What are the symptoms of diabetes?

Diabetes may not cause noticeable symptoms at first. Over time, you may start to notice the symptoms. As well as higher blood sugar levels, general symptoms may include:

Who is Humulin R U-500 prescribed for?

Humulin R U-500 is used to manage blood sugar levels in adults and children with diabetes who need more than 200 units of insulin per day. It’s used on its own, without other types of insulin.

Humulin R U-500 is used to manage blood sugar levels in certain adults and children with diabetes.

How does Humulin R U-500 work?

With diabetes, your body either doesn’t make enough insulin or can’t effectively use the insulin that it makes.

Humulin R U-500 works as a replacement for your body’s natural insulin hormone. The active ingredient in Humulin R U-500 is recombinant human insulin. Recombinant means it’s an exact copy of natural human insulin, that’s made in a lab.

Humulin R U-500 works by moving sugar from foods out of your blood and into your cells. Once inside your cells, sugar can be used as energy or stored. This lowers the amount of sugar in your blood.

The use of Humulin R U-500 can help keep your blood sugar levels within a healthy range. Your doctor or pharmacist can tell you more about how Humulin R U-500 works.

Before you use Humulin R U-500, there’s some important information to keep in mind. The drug may not be a safe option if you have certain medical conditions or other factors that affect your health. Some of these are mentioned below.

If any of the following medical conditions or other health factors apply to you, talk with your doctor before using Humulin R U-500:

  • if you have heart failure and also take certain diabetes medications, such as:
  • if you take other medications, herbs, or supplements that affect your blood sugar levels
  • if you have kidney problems or liver problems
  • if you’re pregnant or breastfeeding
  • if you’ve had an allergic reaction to Humulin R U-500 or any of its ingredients

Talk with your doctor about using Humulin R U-500 for diabetes. They can help determine if Humulin R U-500 might be a good fit for you.

Here are some examples of questions you may want to ask your doctor:

  • What are my goal blood sugar levels?
  • How often should I check my blood sugar levels while using Humulin R U-500?
  • Will I need insulin injections such as Humulin R U-500 to manage my blood sugar levels for the rest of my life?
  • Should I stop using other long-acting insulin when I start using Humulin R U-500?
  • How can I help prevent my blood sugar levels from becoming too low with Humulin R U-500?

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.