Evenity (romosozumab-aqqg) and Prolia (denosumab) are prescription drugs used to treat osteoporosis in certain people. Prolia has other uses as well. Evenity and Prolia are biologics that are not available as biosimilar drugs.

Evenity and Prolia are used to treat this osteoporosis in certain females* who have gone through menopause.

Both Evenity and Prolia come as a liquid solution that a healthcare professional gives as an injection under your skin. These medications can cause many of the same side effects.

This article explains the main ways that Evenity and Prolia are alike and different. For more information about these drugs, including details about their uses, see the in-depth articles on Evenity and Prolia.

Note: The reason “-aqqg” appears at the end of the drug’s name is to show that the drug is distinct from similar medications that may be created in the future.

* In this article, we use the terms “female” and “male” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.

Whether you have health insurance or not, cost may be a factor when you’re considering Evenity or Prolia.

To find out how much you may pay for these drugs, talk with your doctor or pharmacist. But keep in mind that what you’ll pay will depend on your treatment plan, health insurance coverage, and the pharmacy you use. It may also depend on the cost of the visit to a healthcare professional to receive doses of Evenity or Prolia.

Evenity and Prolia are both brand-name biologic drugs. A biologic is made from parts of living organisms.

These drugs aren’t available in biosimilar forms. (Biosimilars are like generic drugs. But unlike generics, which are made for nonbiologic drugs, biosimilars are made for biologic drugs.) Biosimilars are considered to be just as safe and effective as their parent drug. And like generics, biosimilars tend to cost less than brand-name medications.

For resources that might help you save on the price of the drugs, see these articles on Evenity and Prolia.

Evenity and Prolia may not be right for you if you have certain medical conditions or other factors that affect your health. Considerations about who should not use Prolia or Evenity are often referred to as warnings.

The two drugs share some of the same warnings, but they also have different ones. Some of these are mentioned below. Before you start using Evenity or Prolia, talk with your doctor about whether any of these warnings apply to you.

Boxed warning for Evenity: Risk of stroke, heart attack, or death from heart and blood vessel problems

Evenity has a boxed warning. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous.

Evenity can cause heart attack, stroke, or death due to cardiovascular (heart and blood vessel) problems. Your risk of these side effects may be higher if you have certain risk factors, including a history of heart attack or stroke, or if you have type 2 diabetes.

If you receive Evenity, you should watch for symptoms of heart attack and stroke during treatment. The chart below lists some of these symptoms. Your doctor can discuss with you other symptoms of these side effects.

Heart attack symptomsStroke symptoms
sudden, severe chest pain or pressurenumbness or weakness in your face or limbs, usually on one side of your body
lightheadednessloss of balance
shortness of breathheadache
vision loss

Due to the risk of these serious side effects, doctors usually won’t prescribe Evenity to anyone who has had a stroke or heart attack within the past year.

Also, if you have a heart attack or stroke while receiving Evenity, your doctor will stop your treatment.

Boxed warning for Prolia: Severely low blood calcium levels in people with advanced kidney disease

Prolia has a boxed warning. A boxed warning is the most serious warning from the FDA. A boxed warning alerts doctors and patients about drug effects that may be dangerous.

Prolia can cause low blood calcium levels in people with advanced kidney disease. This side effect was also reported with Evenity, but only Prolia has a boxed warning for the increased risk of severely low blood calcium levels, if it’s given to certain people.

If you receive Prolia, you should watch for symptoms of low blood calcium levels during treatment. Your doctor can discuss symptoms of this side effect with you, but here are some examples:

Talk with your doctor if you have chronic kidney disease. They’ll likely recommend that you be tested for certain mineral and bone conditions. These conditions can increase the risk of severely low blood calcium levels with Prolia treatment.

Depending on your specific situation, your doctor may still prescribe Prolia, and they’ll monitor you for symptoms of this risk while you receive the drug. In other cases, they may recommend another treatment for your condition.

Other warnings

In addition to boxed warnings, Evenity and Prolia have other warnings.

Before using Evenity or Prolia, talk with your doctor if any of the following conditions or health factors apply to you.

  • Warnings for Prolia:
    • if you’ve had thyroid or parathyroid surgery (glands in your neck)
    • if your body has difficulty absorbing minerals
    • if you have a weakened immune system
  • Warnings for both Evenity and Prolia:
    • if you’ve had an allergic reaction to either drug or any of its ingredients
    • if you’re pregnant or planning to become pregnant
    • if you’re breastfeeding or planning to breastfeed
    • if you have kidney problems or are receiving dialysis
    • if you have a low blood calcium level
    • if you can’t take a calcium and vitamin D supplement
    • if you have or have had jaw problems
    • if you have plans for dental surgery or to have teeth removed

To learn more about the warnings for these drugs, see our in-depth articles on Evenity and Prolia.

Get answers to some frequently asked questions about Evenity and Prolia.

How do Evenity and Prolia compare with Reclast?

Evenity, Prolia, and Reclast (zoledronic acid) are all prescribed to treat osteoporosis in certain females who have gone through menopause. Prolia and Reclast are also prescribed to prevent or treat other conditions.

Unlike Evenity and Prolia, you receive Reclast as an intravenous (IV) infusion. (This means the drug is slowly injected into a vein over time.) The dosing schedules for these drugs are as follows:

  • Reclast: once per year or once every 2 years, depending on its use
  • Evenity: once per month
  • Prolia: once every 6 months

Treatment with Evenity is limited to 12 months, while treatment with Reclast usually lasts 3 to 5 years. There’s no recommended limit on how long you may receive Prolia.

To learn more about how these drugs compare and which may be right for you, talk with your doctor or pharmacist.

Is Evenity safer than Prolia?

Studies of Evenity and Prolia indicate both are safe for treating osteoporosis in certain females who have gone through menopause. To learn more, check out the “What are the side effects of Evenity and Prolia?” section below.

Some people may have a higher risk of certain side effects from Evenity or Prolia. For example, having certain medical conditions can raise your risk of side effects from either medication. To learn more, see the “What are the warnings for Evenity and Prolia?” section above.

To find out whether Evenity or Prolia may be safer for your condition, talk with your doctor or pharmacist.

What is a good substitute for Prolia and Evenity?

If your doctor suggests treatment with Evenity or Prolia, you may also wonder about other options for treating your condition.

Other medications for treating osteoporosis in certain females who have gone through menopause include:

To learn more about alternatives to Evenity and Prolia, talk with your doctor or pharmacist.

You may wonder if Evenity or Prolia is available as a biosimilar.

Biosimilars are like generic drugs. But unlike generics, which are made for nonbiologic drugs, biosimilars are made for biologic drugs. (A biologic is made from parts of living organisms.)

To find out if Evenity or Prolia is available as a biosimilar, see the lists below.

  • Evenity:
    • Available as a biosimilar: no
    • Active ingredient:* romosozumab-aqqg
  • Prolia:
    • Available as a biosimilar: no
    • Active ingredient: denosumab

* An active ingredient is what makes a drug work.

Both Evenity and Prolia are used to treat osteoporosis in certain females who have gone through menopause. Specifically, doctors will prescribe these drugs to treat osteoporosis in females who have a high risk of broken bones.

In the case of Evenity, this drug may also be used in females who:

  • cannot tolerate other treatments for osteoporosis
  • tried other treatments that didn’t work

Osteoporosis causes bones to become thin and weak, which increases the risk of broken bones. Both Evenity and Prolia work to increase bone mass and strengthen bones.

Prolia also has other uses. These include:

  • increasing bone mass in females receiving certain treatments for breast cancer
  • treating osteoporosis in males
  • increasing bone mass in males receiving certain treatments for certain kinds of prostate cancer
  • treating osteoporosis caused by long-term use of a group of drugs called glucocorticoids, such as Rayos (prednisone)

For details about the uses of these drugs, see our in-depth articles on Evenity and Prolia.

Here’s an overview of the dosage for Evenity and Prolia and how you receive either drug for the condition they both treat: osteoporosis in certain females who have gone through menopause. Note that the strength of both drugs is in milligrams (mg) per milliliter (mL) of solution.

Dosage for osteoporosis

Evenity for osteoporosisProlia for osteoporosis
Formliquid solution for injection under the skinliquid solution for injection under the skin
Strength105 mg/1.17 mL60 mg/1 mL
Dose210 mg60 mg
How often to receiveonce per month for up to 12 monthsevery 6 months

A healthcare professional will give you injections of either drug. They may inject doses under the skin of your abdomen, thigh, or upper arm.

To learn more about the dosages of these drugs, see these articles on Evenity and Prolia.

You may experience mild or serious side effects from Prolia or Evenity. Mild side effects are more common than serious side effects with either drug.

The charts below describe mild and serious side effects that Evenity and Prolia may cause. For more information about possible side effects, see these articles on Evenity and Prolia.

Mild side effects

Evenity and Prolia may cause mild side effects in some people. The chart below lists examples of mild side effects reported with these drugs.

EvenityProlia*
back pain
headache
insomnia (difficulty sleeping)
itching, numbness, or feeling as if your skin is crawling
joint pain
muscle cramps
neck pain
pain in your arms and legs
reactions at the site where the drug is injected, such as pain
swelling in your hands, feet, or lower legs
weakness

* Studies of Prolia reported headache and joint pain. But these side effects didn’t occur when the drug was used to treat osteoporosis in certain females who have gone through menopause.

This chart may not include all mild side effects of these drugs. For more information on mild side effects of the two drugs, see the Evenity prescribing information and Prolia prescribing information.

Serious side effects

In addition to the mild side effects described above, serious side effects may occur in people using Evenity or Prolia. See the chart below for a list of side effects reported with these drugs.

EvenityProlia
unusual bone breaks in your thigh
increased risk of bone fractures (breaks) after stopping treatment
increased risk of heart attack, stroke, or death due to cardiovascular problems*
serious infection, such as serious urinary tract infection (UTI)
low blood calcium level
severe pain in the muscles, joints, or bones
skin problems, such as eczema
decreased bone production (the bones take longer to create new bone tissue)
osteonecrosis (dead bone tissue) of the jaw
allergic reaction

* Evenity has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “What are the warnings for Evenity and Prolia?” section above.
† Prolia has a boxed warning for the increased risk of severely low blood calcium levels in certain people. To learn more, see the “What are the warnings for Evenity and Prolia?” section above.

To learn more about your risk of serious side effects from Evenity or Prolia, talk with your doctor.

You may wonder whether Evenity and Prolia are effective at treating your condition. They’re both prescribed to treat osteoporosis in certain females who have gone through menopause.

American Association of Clinical Endocrinologists (AACE) guidelines recommend both Evenity and Prolia as treatment options for this use.

If you’d like to read more about how each drug performed in studies, see the prescribing information for Evenity and Prolia.

The short answer: It’s possible.

Details: Evenity and Prolia are both prescribed to treat osteoporosis in certain females who have gone through menopause. If you’re receiving Evenity or Prolia for this use, it may be possible to switch to the other medication. Your doctor can provide more information on whether it’s safe for you to do so.

Keep in mind that treatment with Evenity for more than 12 months is not recommended. Doctors will often prescribe Prolia to those who finish treatment with Evenity, if Prolia is safe for them to receive. Studies found this to be an effective way to treat osteoporosis.

If you need to stop receiving Evenity earlier than 12 months, your doctor may also recommend switching to Prolia to treat your osteoporosis.

Reminder: You should not switch drugs or stop your current treatment unless your doctor recommends it.

If you need treatment for osteoporosis, your doctor may recommend Evenity or Prolia. They’re both prescribed for treating this condition in certain females who have gone through menopause. Prolia is also prescribed to treat other conditions, including osteoporosis in males.

Evenity has a boxed warning* about the risk of heart attack, stroke, or death due to cardiovascular (heart and blood vessel) problems. Studies of Prolia didn’t report these side effects. Another key difference between these drugs is that treatment with Evenity is limited to 12 months. Doctors will often prescribe Prolia to those who finish treatment with Evenity.

If you’re interested in learning more about Evenity and Prolia, talk with your doctor. They can answer questions you may have to help you feel more informed about your treatment options. Here are a few examples to get you started:

  • Should I use Evenity for 12 months and then switch to Prolia?
  • If I have side effects from Evenity or Prolia, is it safe for me to try the other medication?
  • How will you determine whether Evenity or Prolia is safer for me?
  • Given my insurance coverage, will one drug be less expensive than the other?

To learn more about Evenity or Prolia, see these articles:

To get information on different conditions and tips for improving your health, subscribe to any of Healthline’s newsletters. You may also want to check out the online communities at Bezzy. It’s a place where people with certain conditions can find support and connect with others.

* This is the most serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous. To learn more, see the “What are the warnings for Evenity and Prolia?” section above.

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.