Key takeaways:
Forteo (teriparatide) and Prolia (denosumab) are osteoporosis injections. They have several differences, including how they work and are administered.
Forteo is a daily injection that you can give to yourself at home. Prolia is administered by a healthcare professional every 6 months.
Forteo and Prolia have different risks and side effects. Forteo’s labeling warns of a rare bone cancer risk. Prolia can cause severely low calcium risks.
There are ways to save on Forteo and Prolia. If you’re eligible, manufacturer savings cards can help make your prescription more affordable. A patient assistance program for Forteo is also available.
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If you have osteoporosis, chances are that your prescriber recommended an oral medication to help protect your bones. But many people find the side effects from these pills bothersome. In this case, your prescriber may suggest trying an osteoporosis injection.
Forteo (teriparatide) and Prolia (denosumab) are two injectable osteoporosis treatments. They both work well for protecting your bones from fractures (breaks). But there are several differences between them, including how they work and are administered.
So what do you need to know when comparing Forteo versus Prolia?
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Forteo vs. Prolia at a glance
The table below highlights some key differences between Forteo and Prolia.
Forteo | Prolia | |
|---|---|---|
Active ingredient | Teriparatide | Denosumab |
Is it a biologic medication? | No | Yes |
Medication class | Parathyroid hormone (PTH) analog | RANK ligand (RANKL) inhibitor |
FDA-approved uses | • Osteoporosis in women at high risk for fractures who have gone through menopause • Osteoporosis in men at high risk for fractures • Osteoporosis that’s caused by long-term corticosteroid (steroid) treatment for people at high risk for fractures | • Osteoporosis in women at high risk for fractures who have gone through menopause • Osteoporosis in men at high risk for fractures • Osteoporosis that’s caused by long-term steroid treatment for people at high risk for fractures • Bone loss in men who are taking certain medications for prostate cancer and are at high risk for fractures • Bone loss in women who are taking certain medications for breast cancer and are at high risk for fractures |
Dosage | 20 mcg injected subcutaneously (under the skin) once a day | 60 mg injected under the skin every 6 months |
How packaged | Multidose injection pen that contains 28 doses (28-day supply) | Prefilled, single-dose syringe |
Can you inject the medication yourself? | Yes | No, must be injected by a healthcare professional |
How long can you use it? | Up to 2 years* | Long term |
Common side effects | • Muscle pain • Joint pain • Nausea • Runny nose • Weakness • Headache • Raised blood pressure • Constipation or diarrhea • Cough • Sore throat | • Back pain • Pain in the extremities (arms or legs) • Muscle pain • Raised cholesterol • Dizziness • Bladder infections • Upper respiratory tract infections • Swelling in the arms or legs • Stomach pain |
Rare risks | • High calcium levels • Calciphylaxis (potentially life-threatening calcium buildup in the blood vessels) • Kidney stones • Bone cancer (seen in animal studies) • Allergic reactions | • Low calcium levels • Osteonecrosis of the jaw (breakdown of the jaw bone) • Higher risk of fractures if you stop using Prolia • Serious infections • Severe muscle, joint, or bone pain • Skin-related reactions, such as eczema • Allergic reactions |
*This is the manufacturer’s recommended length of use for Forteo. Your prescriber may suggest using it for more or less time than this.
Here are five differences to keep in mind when comparing Forteo versus Prolia.
1. Forteo and Prolia work in different ways
A key difference between Forteo and Prolia is how they work.
Forteo is a PTH analog. This means it works like PTH, a bone-building hormone your body makes. Forteo helps promote new bone growth and raise your bone mineral density. This can help strengthen your bones and lower your risk of fractures.
Prolia is a RANKL inhibitor. It blocks the activity of a protein in your body called RANKL. This protein’s job is to help break down bone cells. By blocking RANKL, Prolia helps prevent bone loss and lowers your risk of fractures.
Good to know: Prolia is a biologic medication. Forteo is a small molecule drug. Biologics are more expensive to produce, so they often cost more than small molecule drugs. Biologics also carry certain risks, such as a higher risk of infection, that many small molecule drugs don’t have.
2. Forteo and Prolia have different approved uses
Forteo and Prolia also have different approved uses. Both are approved to treat:
Osteoporosis in women at high risk for fractures who have gone through menopause
Osteoporosis in men at high risk for fractures
Osteoporosis that’s caused by long-term steroid use for people at high risk for fractures
Prolia has two additional approved uses. It can be used to treat:
Bone loss in men at high risk for fractures that’s caused by androgen-blocking medications for prostate cancer
Bone loss in women at high risk for fractures that’s caused by aromatase inhibitors for breast cancer
Your health history can determine why your prescriber may recommend one over the other.
3. Forteo is a daily injection, while Prolia is injected every 6 months
Forteo and Prolia have different dosage schedules.
Forteo is a once-daily injection. It comes as a multidose injection pen that contains 28 doses for a 28-day supply. After your healthcare team shows you how to use the device, you can inject Forteo yourself.
Prolia is an injection that you’ll receive once every 6 months. It comes as a prefilled syringe that contains enough medication for 1 dose. Unlike Forteo, you can’t inject Prolia by yourself. You’ll need to get the injection from a healthcare professional at a medical office or a clinic.
How often you’ll need injections and where you receive them may help you choose between Forteo and Prolia. Be sure to tell your prescriber if you have a preference. This can help them pick the osteoporosis injection that’s right for you.
4. Prolia can be used long term, while Forteo is usually used for only 2 years
How long you’ll need treatment is another factor to keep in mind when comparing Forteo and Prolia.
Research suggests that Prolia can be given safely for at least 10 years. And the American College of Physicians (ACP) supports the long-term use of the medication. So as long as Prolia is working well and not causing too many side effects, your prescriber will likely suggest continuing it.
Forteo is not recommended for long-term use. The manufacturer suggests limiting treatment to no more than 2 years. This is to help limit some of the rare but serious side effects of the medication (more on this below). The ACP also states that the long-term use of Forteo hasn’t been well studied. So they don’t recommend it for most people.
Keep in mind that your prescriber may recommend using Forteo for longer or shorter than 2 years. They’ll take your health history and fracture risk into account. So be sure to follow their instructions, even if they’re different from what Forteo’s manufacturer and the ACP suggest.
5. Forteo and Prolia have different side effects
Because they work differently, Forteo and Prolia have distinct side effects. The table below highlights some of the side effects for each medication. Keep in mind these aren’t complete lists of all possible side effects.
Common: • Muscle pain • Joint pain • Nausea • Runny nose • Weakness • Headache • Raised blood pressure • Constipation or diarrhea • Cough • Sore throat Rare: • High calcium levels • Calciphylaxis (potentially life-threatening calcium buildup in the blood vessels) • Kidney stones • Bone cancer (seen in animal studies) • Allergic reactions | Common: • Back pain • Pain in the arms or legs • Muscle pain • Raised cholesterol • Dizziness • Bladder infections • Upper respiratory tract infections • Swelling in the arms or legs • Stomach pain Rare: • Higher risk of fractures if you stop using Prolia • Serious infections • Severe muscle, joint, or bone pain • Skin-related reactions, such as eczema • Allergic reactions |
Below is more information on two notable side effects that are very rare.
Forteo and bone cancer
Forteo has a rare risk for osteosarcoma (a type of bone cancer). This is based on animal studies. Human studies have not confirmed this risk. But the manufacturer takes this very seriously. This is why they recommend that most people use Forteo only for up to 2 years in their lifetime.
The manufacturer also recommends avoiding Forteo if you:
Are living with a health condition that raises your risk of bone cancer, such as Paget’s disease
Have a history of bone cancer
Have ever received bone radiation treatments
Prolia and low calcium
Prolia has a boxed warning for severely low calcium levels. A boxed warning is the FDA’s strictest warning for medications. In some cases, your calcium levels may become dangerously low. Your risk for this serious side effect may be higher if you have advanced chronic kidney disease.
Prolia’s manufacturer suggests taking at least 1,000 mg of calcium and at least 400 IU of vitamin D per day. This can help prevent this side effect. Ask your prescriber if you should take more or less of these supplements.
Your healthcare team should request routine blood tests to watch your calcium levels. Be sure to go for these tests on time. This helps your prescriber watch for signs of this serious Prolia side effect.
How to save on Forteo and Prolia
There are ways to save on Forteo and Prolia. GoodRx can help you navigate between GoodRx coupons, copay savings cards, and patient assistance programs to save money on your prescription.
Save with GoodRx. GoodRx can help you save over 65% off the average retail price of the generic version of Forteo.
Save with a copay savings card. If you have commercial insurance, you may be eligible to pay as little as $4 per 28-day supply for brand-name Forteo or $0 per injection for Prolia using a savings card from the manufacturers.
Save with patient assistance programs. If you’re uninsured or underinsured, you may be eligible for Forteo’s patient assistance program, which offers the medications free of cost.
Save with a Prolia biosimilar. Depending on your location and situation, you may be eligible for a biosimilar version of Prolia. Your prescriber can tell you more about Jubbonti, Conexxence, and other Prolia biosimilars if applicable.
Frequently asked questions
Small studies have found that people can safely use Prolia after Forteo. But larger studies are needed to confirm if this is safe for most people. Your prescriber can help you decide if using Prolia after Forteo would be appropriate for you.
The combination of Prolia and Forteo hasn’t been well studied. But limited research suggests that using both may help increase BMD more than either can alone. More studies are needed to say whether this combination is safe or works well for most people. Depending on your fracture risk, your prescriber may explore whether using Prolia and Forteo together is an option for you.
Small studies have found that people can safely use Prolia after Forteo. But larger studies are needed to confirm if this is safe for most people. Your prescriber can help you decide if using Prolia after Forteo would be appropriate for you.
The combination of Prolia and Forteo hasn’t been well studied. But limited research suggests that using both may help increase BMD more than either can alone. More studies are needed to say whether this combination is safe or works well for most people. Depending on your fracture risk, your prescriber may explore whether using Prolia and Forteo together is an option for you.
The bottom line
Forteo (teriparatide) and Prolia (denosumab) are osteoporosis injections. They work differently to help lower your risk of fractures (bone breaks). Forteo is a daily injection you can give to yourself. Prolia is an injection that’s administered by a healthcare professional every 6 months.
Forteo and Prolia have different side effects and risks to consider. Forteo has a rare risk of bone cancer. Prolia can cause severely low calcium. Discuss these osteoporosis injections with your prescriber to see if one is an option for you.
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References
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