Medications for osteoporosis
Our bodies work constantly to maintain a balance between the formation of new bone and the breakdown of old bone. When we are young, the body forms bone faster than it breaks it down, which results in increasing bone mass. As we age, this process slows down, causing more loss of bone than the building of bone. Both men and women are affected by osteoporosis. However, certain ethnicities are more at risk for bone loss than others, as are women after menopause, and all of us are more prone to osteoporosis with increasing age. This balance between bone loss and bone formation is of interest when it comes to medications and other treatment options for osteoporosis.
There are various treatments for osteoporosis, including both pills and injectable therapies, that can reduce the risk of bone loss and fractures significantly. If you are unsure of where to start, be sure to discuss all options with your doctor so that he or she can tailor the medication to you, your bone density and your personal history. Outlined below are some common osteoporosis treatments, with their risks and benefits.
Is medication the only treatment for osteoporosis?
Medication is standard for treating osteoporosis, although there are lifestyle changes you should make, too. For example, eating healthy, walking, resistance training, and ensuring adequate vitamin D stores as well as daily intake of calcium can all help improve bone mineral density.
Depending on the severity of the osteoporosis, your medical history and your history of fractures, your doctor might recommend osteoporosis medication to prevent further bone loss. Osteoporosis cannot be cured, but these medications can help with reduction of fracture risk and improving your bone health. Some osteoporosis medications slow or prevent bone loss, while others can help build new bone.
Osteoporosis vs. osteopenia
Osteopenia is a condition where an individual’s bone mineral density is lower than the average level for their age and gender and is less severe than osteoporosis. Osteopenia can progress to a diagnosis of osteoporosis, where the bones are weaker and have a higher chance of breaking. With osteopenia, your doctor will likely recommend certain lifestyle changes and supplements to help preserve your current bone density. These lifestyle changes include exercising regularly, ensuring adequate daily calcium intake and vitamin D stores, avoiding certain foods like tobacco and excessive alcohol and caffeine. Not everyone with osteopenia develops osteoporosis and your doctor will monitor your osteopenia with bone density scans usually every 2-3 years.
There are certain situations where you may need to be monitored more frequently including if you are on steroids for an extended period of time, have an overactive thyroid and certain cancer treatments (e.g. aromatase inhibitors for breast cancer). It is also important to note that the diagnosis of osteoporosis can be made even if the bone density shows osteopenia. This occurs when certain fractures (broken bones) indicate weak bone quality and if the individual does not take preventive measures, such as making the lifestyle changes mentioned above. For this, a doctor will most likely educate their patient on eating healthy and exercising instead of getting right into a bone density medication regimen.
Osteoporosis is a disease when bone density is so low that the bones become weaker, putting them at a greater risk of fracturing (breaking). Osteoporosis can vary in severity. The most common osteoporosis-related fractures occur in the hip, wrist or spine.
How are osteoporosis and osteopenia diagnosed?
According to the American Association of Clinical Endocrinologists 2020 Clinical Practice Guidelines for The Diagnosis and Treatment of Postmenopausal Osteoporosis in 2020, osteoporosis can be diagnosed in the setting of a fragility fracture even with a normal bone mineral density scan (T-score). Osteoporosis can also be diagnosed based on a T-score of −2.5 or lower in the lumbar spine, femoral neck, total hip, or 1/3 distal radius wrist. In addition, osteoporosis can be diagnosed in patients with osteopenia using a special calculator called FRAX® (fracture risk assessment tool) to determine your risk of breaking a bone over 10 years.
The score from a bone mineral density (DXA) scan is known as a T-score. Below are some ranges that identify what scores qualify for a diagnosis and severity:
- T-score of 0 means that one’s bone mineral density is the same as a young, healthy adult.
- T-score between +1 and -1 is considered normal.
- T-score between -1 and -2.5 is considered low bone mass, or osteopenia.
- T-score of -2.5 or below is a diagnosis of osteoporosis.
- T-score of -2.5 or lower (a higher negative number) is a more severe case of osteoporosis.
This stratification helps identify and tailor the best choice of an initial medicine for osteoporosis and how long treatment may be needed.
Suppose you have osteopenia or mild osteoporosis (T-score between -1 and -2.5). In that case, your healthcare provider may suggest lifestyle changes as the best treatment to increase bone mineral density and lower the risk of fracture instead of osteoporosis medication.
If you have a more severe case of osteoporosis (T-score of -2.5 or lower) or if you have an osteoporotic fracture regardless of your bone density, you may also be advised to start bone-density medication.
First-line osteoporosis treatments
Bisphosphonates
Often, patients with osteoporosis are first given a class of medications called bisphosphonates. These drugs inhibit an enzyme responsible for bone resorption (the breakdown of bone tissue) and effectively prevent and treat osteoporosis (Watts & Diab, 2010).
Common bisphosphonate drugs include:
- Alendronate (Fosamax): A pill that the FDA approved in 1995
- Risedronate (Actonel, Atelvia): A pill that the FDA approved for the treatment of osteoporosis in 2000
- Ibandronate (Boniva): A pill or intravenous (IV) infusion approved by the FDA in 2005
- Zoledronate (Reclast): An IV infusion approved by the FDA in 2007
Each of these drugs has a unique chemical makeup and potency which varies the rate of onset and the degree of effect.
Denosumab (Prolia)
Denosumab (Prolia) is a different type of medication from a bisphosphonate, called a RANK ligand inhibitor. This type of medication reduces bone resorption and turnover. It is administered via injection. Bisphosphonates are excreted through the urine, so denosumab might also be considered for those with renal disorders. This drug works by blocking bone breakdown. A doctor usually injects it once every 6 months (U.S. National Library of Medicine, n.d.). It is very important to stay on schedule with denosumab and receive it every six months given the risk of rebound vertebral fractures and significant bone loss with skipping a dose. Denosumab cannot be discontinued; it must be transitioned to an alternate osteoporosis treatment such as bisphosphonate.
Common side effects of bisphosphonates
Common side effects of bisphosphonate pills include upset stomach and heartburn. This could be due in part to the fact that these drugs are taken first thing in the morning, only with water, and before food intake. These osteoporosis medications cannot be followed up with any other food or drink for another 30-60 minutes (Watts & Diab, 2010).
Some ways to reduce these side effects include avoiding lying down after taking the medication and ensuring that you take the pill with a big glass of water.
There tend to be fewer stomach side effects with injectable osteoporosis medications. Since they are not taken orally, these medications don't tend to cause an upset stomach. However, Zoledronate, which is given by IV infusion, can cause flu-like symptoms, which can last a few days.
Serious side effects of bisphosphonates
In some rare cases, long-term use of bisphosphonate-containing osteoporosis drugs can cause rare but serious side effects.
Rare but serious side effects include:
- Atypical femoral fracture (low trauma fractures in the thighs)
- Osteonecrosis of the jaw bone (ONJ), the presence of exposed bone in the mouth that does not heal within 8 weeks after identification by a health-care professional
These serious side effects are more likely to occur in patients taking very high doses of bisphosphonate, which is not typical for those diagnosed with osteoporosis
The risk of fracture and ONJ due to bisphosphonate usage increases the longer one takes the medication. Because of this, a healthcare provider may suggest taking a "drug holiday" from bisphosphonates. This is when an individual takes a break from bisphosphonates. A “holiday” may be recommended after taking the medication for 5-10 years or less. However, this break may only last 1-2 years, and the patient may have to supplement with a non-bisphosphonate drug during that time (Watts & Diab, 2010).
Is hormone therapy used for osteoporosis treatment?
Osteoporosis is common in postmenopausal women due to a decrease in hormone production, specifically estrogen and progestin. Hormone replacement therapy is medication that supplements and replaces the loss of estrogen during menopause. It has been proven to reduce the risk of fractures and prevent bone loss in postmenopausal women, however there are also associated risks. These risks include: blood clots, endometrial cancer, breast cancer, and heart disease.
There are numerous factors in determining the risks of hormone treatment including age and prior medical issues. It is important to tailor treatment of hormone replacement therapy and determine if the benefits outweigh the risks.
It is best for those considering hormone replacement therapy to speak with their healthcare provider regarding these pros and cons. In addition to improving bone density and bone health, this type of osteoporosis treatment may help lessen common side effects resulting from menopause, such as reducing hot flashes. Therefore, this effect may be seen as an added perk when weighing treatment options.
Raloxifene (Evista) is a drug that mimics the workings of estrogen. It belongs to a class of drugs called selective estrogen receptor modulators (SERMs), which reduce bone resorption and improve bone mineral density. Although raloxifene’s benefits include improved bone health and decreased risk of breast cancer, it also can cause hot flashes and increase the risk of blood clots (D'Amelio & Isaia, 2013). The degree of risks, pros, and cons will differ from person to person and is best discussed with one’s healthcare provider.
Osteoporosis drugs that help build new bone
Unlike the medications for osteoporosis mentioned above, some drugs aid in the process that is responsible for bone formation. These drugs are called osteoanabolic medications.
Osteoanabolic medications are considered a first-line treatment in patients who are considered to be at a "very high fracture risk," as these are more aggressive treatments that are intended to help achieve an acceptable level of fracture risk. In very high fracture risk patients, there is evidence that osteoanabolic agents are better than antiresorptive medications at reducing spine fracture risk.
Examples of very high fracture risk patients include patients with recent fractures (within the past 12 months), fractures sustained while taking osteoporosis medications, multiple fractures, very low T-score (e.g. less than -3.0), high risk for falls, and very high fracture probability by FRAX.
Abaloparatide, denosumab, romosozumab, teriparatide and zoledronate should only be considered for patients who are unable to use oral therapy and as initial therapy for patients at very high fracture risk according to the AACE 2020 PMO CPG.
3 medications for osteoporosis that help with bone formation
The following three osteoporosis medications help with bone formation: teriparatide (Forteo), abaloparatide (Tymlos) and romosozumab (Evenity).
Although these medications for osteoporosis aid in bone-building, they do not necessarily help with maintaining new bone growth. For that reason, treatment with these drugs must be followed up with an antiresorptive osteoporosis drug to help prevent the breakdown of the new bone (Cohen et al., 2015).
Teriparatide (Forteo) and Abaloparatide (Tymlos)
Teriparatide (Forteo) and abaloparatide (Tymlos) are both considered parathyroid hormone receptor agonist medications, which work by increasing stimulation of bone formation relative to bone resorption. Potential side effects include: nausea, dizziness, headache and heart palpitations. They are both a subcutaneous daily injection.
If someone has previously been on antiresorptive therapy, switching to teriparatide can cause significant hip bone mineral density loss. As a result, some experts recommend osteoanabolic therapy as a first line treatment for osteoporosis in patients at high risk, followed by antiresorptive treatment.
Some data shows that abaloparatide may have less hypercalcemia risk than teriparatide. Abaloparatide does not require refrigeration whereas teriparatide does.
Note that these agents should be avoided in the setting of osteosarcoma, Paget's disease, children, high calcium levels as well as a few other medical conditions.
Because both teriparatide and abaloparatide work on the bone-building processes, there is a hypothesized risk that tumors can form. The "black box" warnings regarding a potential increased risk for osteosarcoma were removed from teriparatide and abaloparatide in 2020 and 2021, respectively.
Romosozumab (Evenity)
Romosozumab (Evenity) is a once a month injection. It is given for a total duration of one year, then must be followed with a drug intended for long-term treatment such as bisphosphonate or denosumab. Romosozumab targets and inhibits a protein called sclerostin, which slows or stops bone formation. Romosozumab works through a unique mechanism of action which has a dual effect on bone by increasing bone formation and decreasing bone resorption.
How a healthcare provider chooses your osteoporosis treatment
Finding the best and safest treatment for osteoporosis in 2024 will depend on several factors. Some include:
- The severity of your osteoporosis
- Your history of prior fracture
- Your risk of falls
- Your gender (some medications are only FDA approved for postmenopausal women, for example)
- Your age
- Your medical history
- Ease of use (IV drugs are administered less often, but a pill may be easier to take)
- Cost (what your insurance will cover)
Is medication for osteoporosis enough?
Regardless of whether you have been prescribed medication for osteoporosis, your doctor will also recommend that you make lifestyle changes to improve your bone health, such as:
- Exercise including resistance training and walking (Rafiq, 2018)
- A diet rich in enough calcium and vitamin D
- Supplements (calcium supplements or vitamin D) when needed (choose a brand recommended by your doctor since these aren't regulated by the FDA)
These lifestyle changes can have a meaningful impact on not just your bone health, but your overall health as well.
A well-rounded exercise program can be a crucial component of your osteoporosis treatment plan. Programs that incorporate strength, balance and posture exercises, like Wellen’s, can be a great starting place to help you build or maintain bone density and prevent falls and fractures.
