Forteo (teriparatide) is used to treat osteoporosis (bone loss or weakening). It's for people who are at very high fracture risk or people who've already tried other osteoporosis medications. Forteo (teriparatide) is an injection that you give to yourself once a day. Some common side effects include general body pain and joint pain. This medication comes as a prefilled pen, but it doesn't come with pen needles. Forteo (teriparatide) is only available as a brand medication; there's no generic version yet.
Osteoporosis in females who've gone through menopause (postmenopause)
Osteoporosis in males
Osteoporosis caused by long-term use of corticosteroids
Forteo (teriparatide) is a parathyroid hormone (PTH) analog, meaning it works similarly to the PTH your body normally makes. PTH is a hormone that's important in balancing bone breakdown and formation to keep your bones healthy.
Forteo (teriparatide) works by promoting bone growth. This helps raise your bone mineral density (BMD), which is a measure of how strong your bones are. A higher BMD means your bones are stronger, which helps lower your risk of bone fractures.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Confusion
headache
incoherent speech
increased urination
loss of appetite
metallic taste
muscle weakness
stomach pain
thirst
unusual tiredness
vomiting
Less common
Arm, back, or jaw pain
chest pain, discomfort, tightness, or heaviness
fainting
fast or irregular heartbeat
fever or chills
sweating
trouble breathing
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Acid or sour stomach
belching
blurred vision
body aches or pain
difficulty having a bowel movement (stool)
difficulty with moving
dizziness
hoarseness
indigestion
lack or loss of strength
muscle pain, stiffness, or spasm
nervousness
pain in the joints
pounding in the ears
runny or stuffy nose
tender, swollen glands in the neck
trouble with swallowing
voice changes
Less common
Back pain
discomfort
discouragement
dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
feeling of constant movement of self or surroundings
feeling sad or empty
indigestion
irritability
lack of appetite
leg cramps
loss of interest or pleasure
neck pain
sensation of spinning
stomach cramps
swollen mouth and tongue
tiredness
tooth disorder
trouble concentrating
trouble sleeping
unpleasant taste
urge to have bowel movement
Incidence not known
Bleeding, blistering, burning, coldness, discoloration of skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
flushing
unusually warm skin
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Can use if you're unable to take or still getting fractures with other osteoporosis medications
A first-choice option for people at very high fracture risk (have had a fracture caused by osteoporosis before or have many risk factors for fracture)
Lowers the risk for back fractures and fractures in other parts of the body (not including the hip) in postmenopausal women with osteoporosis
Not a first-choice option for most people with osteoporosis
Only available as an injection under the skin
Can only use for a total of 2 years throughout your entire life because of unclear risk for bone cancer with longer treatment
Keep Forteo (teriparatide) in the refrigerator except when you need to use it. Use the medication right away after taking it out of the refrigerator. Don't freeze or use if it's been frozen. Forteo (teriparatide) isn't safe to use if it gets too warm or too cold.
Each Forteo (teriparatide) pen can be used for up to 28 days. Throw away the pen 28 days after you first use it even if it's not completely empty.
Use Forteo (teriparatide) while sitting or lying down since it might cause dizziness right after the injection. If you feel dizzy, lie down, and it should go away within a few hours.
Your healthcare provider might tell you to take calcium and vitamin D supplements along with your Forteo (teriparatide) treatment. These supplements can help your bones get stronger.
How to use Forteo (teriparatide)
Before using Forteo (teriparatide), it's important to carefully read the User Guide that comes with the pen. These instructions help you to set up, inject the medication, and clean up safely. Ask your healthcare provider or pharmacist if you have any questions about how to use Forteo (teriparatide).
Clean the area where you'll be injecting into with an alcohol swab to prevent infections. Use a new pen needle every time you use the medication. And don't share your pen or pen needles with anyone else. These steps help prevent infections from spreading as well.
Place a new needle onto the pen and set the dose. Then, inject Forteo (teriparatide) under the skin in your lower stomach or the outer part of your thigh. Inject into different areas each time to prevent skin irritation or damage.
Inject Forteo (teriparatide) under the skin by gently pinching your skin away from your body. Then, push the needle straight into the skin. Press the black button at the top of the pen down until it stops. Slowly count to 5 to make sure all the medication gets into your body. Then, pull the needle straight out.
Once you've injected your dose, remove the needle from the pen. Throw the pen needle away in a sharps container to prevent accidental injuries.
Forteo (teriparatide) 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.
Risk factors: Rickets | Paget's disease | Long bones that are still growing | History of bone cancer or cancer that has spread to the bones | Previous radiation therapy to the bones | Inherited conditions with higher risk of bone cancer
Some people taking Forteo (teriparatide) have developed a type of bone cancer called osteosarcoma. Because it's so rare, it's unclear if the risk of getting bone cancer is higher if you use the medication. To be extra careful, Forteo (teriparatide) shouldn't be used in people with certain bone conditions or people who are at a higher risk of bone cancer. There's not enough information to know about the risk of osteosarcoma when people use the medication for more than 2 years. So, your healthcare provider will discuss with you about stopping Forteo (teriparatide) after 2 years of treatment.
Risk factors: Conditions that can raise your calcium levels | History of high PTH levels in the blood
Forteo (teriparatide) can cause high calcium levels in your blood. If you already have a condition that can cause high calcium levels, avoid taking this medication because it can worsen this problem. Tell your healthcare provider about the medical conditions you have before starting Forteo (teriparatide). And if you experience tiredness, irregular heartbeat, muscle weakness, constipation, or loss of appetite while you're taking Forteo (teriparatide), speak with your provider. These can be symptoms of high calcium levels.
In addition, too much calcium in the blood can break down skin. It can also cause the calcium to clump together and block blood from flowing to other parts of the body. If you have an autoimmune condition, kidney failure, or if you're also taking Forteo (teriparatide) with warfarin (Coumadin) or oral corticosteroids (e.g., prednisone), you might be at higher risk for this serious complication. Stop taking Forteo (teriparatide) and tell your healthcare provider right away if you see a new or worsening ulcer on your skin, particularly on your thighs or buttocks.
Risk factors: History of kidney stones | History of high calcium levels in your urine
In studies, some people taking Forteo (teriparatide) had kidney stones. Sometimes, kidney stones can form if the calcium levels in your blood and urine are too high. Before starting this medication, let your healthcare provider know if you currently have a kidney stone or if you have high calcium levels in your urine. Your condition might worsen with Forteo (teriparatide) treatment. Contact your provider as soon as possible if you have severe lower back or side pain, nausea, vomiting, or urine that's bloody or darker, cloudier, or smellier than usual. These can be symptoms of a kidney stone.
While you're taking Forteo (teriparatide), you might have a drop in blood pressure when you stand up after sitting or lying down. This can make you feel dizzy or lightheaded. This drop in blood pressure typically happens during the first few times you take Forteo (teriparatide), but it gets better as you get used to the medication. And when it happens, it's usually within 4 hours of the injection. Sit or lie down when you inject, in case you feel dizzy or feel your heart racing. If you have these symptoms after injecting, lie down. The symptoms should go away within a few minutes to a few hours. If the symptoms don't go away or get worse, talk to your healthcare provider before you continue using Forteo (teriparatide).
Risk factors: Taking digoxin (Lanoxin) at the same time as Forteo (teriparatide)
Taking Forteo (teriparatide) together with the heart medication digoxin (Lanoxin) can possibly raise your risk of the toxic effects of digoxin (Lanoxin). Both Forteo (teriparatide) and digoxin (Lanoxin) can raise the calcium levels in your body. Because of this, Forteo (teriparatide) can boost the effects that digoxin (Lanoxin) has on the body. This can cause stomach upset, changes in vision, and irregular heart rhythms. If you're taking Forteo (teriparatide) and digoxin (Lanoxin), talk to your healthcare provider if you feel a slower or faster than usual heartbeat at any time during treatment.
The typical dose is 20 mcg injected once a day under the skin of your lower stomach or outer part of your thigh.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Osteoporosis in females who've gone through menopause (postmenopause)
Osteoporosis in males
Osteoporosis caused by long-term use of corticosteroids
Osteoporosis in women who have gone through menopause (postmenopause)
Osteoporosis in men
Osteoporosis in females who've gone through menopause
Osteoporosis in males
Osteoporosis caused by certain steroid medications
Bone loss in males taking certain medications for prostate cancer
Bone loss in females taking certain breast cancer medications
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MedlinePlus. (n.d.). Bone density.
Eli Lilly and Company. (2021). FORTEO- teriparatide injection, solution [package insert]. DailyMed.
Camacho, P. M., et al. (2020). American Association of Clinical Endocrinologists/American College of Endocrinology clinical practice guidelines for the diagnosis and treatment of postmenopausal osteoporosis – 2020 update. Endocrine Practice.
Eli Lilly and Company. (2019). FORTEO teriparatide injection: User manual.
FORTEO teriparatide injection. (n.d.). Learn how to inject with FORTEO (teriparatide injection).
American Cancer Society. (2020). What is osteosarcoma?
Leder, B. Z., et al. (2009). Effects of teriparatide treatment and discontinuation in postmenopausal women and eugonadal men with osteoporosis. The Journal of Clinical Endocrinology and Metabolism.
Leder, B. Z. (2018). Optimizing sequential and combined anabolic and antiresorptive osteoporosis therapy. JBMR Plus.
Westphal, S. G., et al. (2022). Calciphylaxis. StatPearls.
Cummings, E. D., et al. (2023). Digoxin toxicity. StatPearls.
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