Tymlos (abaloparatide) is a prescription drug that’s used to treat osteoporosis. Tymlos can cause mild to serious side effects. Examples include dizziness, injection site reactions, and nausea.

Tymlos is used to treat osteoporosis in adults who have a high risk of bone fracture (such as postmenopausal people) for whom other treatments haven’t worked.

Tymlos comes as a liquid solution inside a prefilled pen. It’s given as an injection under the skin. Tymlos contains the active ingredient abaloparatide. (An active ingredient is what makes a drug work.)

Keep reading to learn about the common, mild, and serious side effects Tymlos can cause. For a general overview of the drug, including details about its uses, see this article.

Below are a few of the more common side effects reported by people who took Tymlos in studies. Side effects can vary depending on the condition the drug is being used to treat.

More common side effects in postmenopausal females* undergoing treatment with Tymlos include:

More common side effects in males* undergoing treatment with Tymlos to increase bone mineral density include:

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

Mild side effects have been reported with Tymlos. These include:

In most cases, these side effects should be temporary. And some may be easily managed. But if you have symptoms that are ongoing or bothersome, talk with your doctor or pharmacist. And do not stop Tymlos treatment unless your doctor recommends it.

Tymlos may cause mild side effects other than those listed above. See the drug’s prescribing information for details.

* To learn more about this side effect, see the “Side effects explained” section below.

While rare, serious side effects have been reported with Tymlos. These include:

To learn more about these side effects, see the “Side effects explained” section below.

If you develop serious side effects during Tymlos treatment, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

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 Tymlos, visit MedWatch.

Get answers to some frequently asked questions about Tymlos’s side effects.

Can Tymlos cause hair loss?

No, it’s not expected to. Hair loss wasn’t reported as a side effect in studies of Tymlos.

Talk with your doctor if you experience hair loss or have concerns about it. They can review your medications and determine whether any of them could be causing your symptoms.

How long do side effects of Tymlos usually last?

It depends. In most cases, side effects caused by Tymlos are temporary. Mild side effects usually go away on their own within a few hours to days for most people.

In rare instances, side effects of Tymlos may last longer. For example, some rare but serious side effects caused by Tymlos may be long term or cause long-term complications. These side effects include:

To learn more about these side effects, see the “Side effects explained” section below.

Talk with your doctor or pharmacist if you have more questions or concerns about side effects from Tymlos.

Learn more about some of the side effects Tymlos may cause.

High calcium level in your blood or urine

Tymlos can cause hypercalcemia (a high calcium level in your blood) or hypercalciuria (a high calcium level in your urine) as a side effect. While rare in studies, this side effect is considered serious.

Mild hypercalcemia often does not cause symptoms. But it’s possible to experience the following, especially if the condition worsens:

There are no specific symptoms for hypercalciuria, but the condition increases your risk of kidney stones. Symptoms of kidney stones can include:

What might help

Before and during treatment, your doctor will likely order tests to check the level of calcium in your blood and urine. They can provide more information on how frequently you’ll need these tests during Tymlos treatment.

If you think you have symptoms of hypercalcemia or kidney stones, contact your doctor right away. They can evaluate your symptoms and recommend the best treatment. This may include stopping Tymlos.

Possible risk of bone cancer

Treatment with Tymlos may increase your risk of bone cancer, although more research is needed. Symptoms of bone cancer can include:

  • pain and swelling in the affected bone(s)
  • a hard mass you can feel in a long bone, such as in your pelvis or limbs
  • pain in your bones that interrupts your sleep
  • decreased range of motion in the affected bone(s)
  • fever and weight loss (in rare cases)

What might help

Due to the possible risk of bone cancer, doctors will usually not prescribe Tymlos for people who are already at high risk. This includes those who have:

  • a metabolic bone disease besides osteoporosis, such as Paget’s disease
  • a history of bone cancer or another cancer that has metastasized (spread) to the bones
  • received radiation therapy or external beam treatment that involves the skeleton

During Tymlos treatment, contact your doctor if you notice any symptoms described above. They can review your symptoms and, if needed, order more tests to check for bone cancer.

Low blood pressure when changing positions

Tymlos can cause you to experience low blood pressure when changing positions, such as sitting or standing up. Symptoms of this side effect can include any of the following when changing positions:

While uncommon, this side effect can be dangerous. It may lead to falling or fainting, which may result in other injuries, such as broken bones.

What might help

Due to this potential side effect, you should inject your first several Tymlos doses in a setting where you can lie down quickly. This could be a place such as your bedroom or on a couch. You should continue doing this until you know how the drug will affect you.

Let your doctor know if this side effect continues during your Tymlos treatment. They can review your symptoms and check for other possible causes. if your symptoms don’t go away, they may suggest stopping Tymlos and exploring other osteoporosis treatment options.

Bone pain

Although it’s uncommon, bone pain was a side effect reported in Tymlos studies. It can also be a symptom of rare but serious side effects caused by Tymlos. These include bone cancer and a high level of calcium in your blood or urine.

What might help

Because it can be a symptom of rare but serious side effects, let your doctor know right away if you experience bone pain while using Tymlos. Your doctor can review your symptoms and, if needed, order more tests to check whether bone pain is a symptom of a more serious side effect caused by the drug.

Allergic reaction

Like most drugs, Tymlos can cause an allergic reaction in some people. This side effect wasn’t reported in studies, but there have been reports since Tymlos was approved for use.

Symptoms can be mild to serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin (usually in your eyelids, lips, hands, or feet)
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms. Examples include:

If your doctor confirms you’ve had a mild allergic reaction to Tymlos, they’ll decide whether you should continue using it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Tymlos, they may have you switch to a different treatment.

Keeping track of side effects

During your Tymlos treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start taking a new drug or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were taking when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how your symptoms affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Taking notes and sharing them with your doctor will help them learn more about how Tymlos affects you. They can then use this information to adjust your treatment plan if needed.

Tymlos may not be right for you if you have certain medical conditions. This is known as a drug-condition interaction. Other factors may also affect whether this drug is a good treatment option for you. Talk with your doctor about your health history before starting Tymlos. Factors to consider include those described below.

Bone disease (besides osteoporosis), such as bone cancer or Paget’s disease. Having certain bone diseases, including Paget’s disease, increases your risk of bone cancer. And treatment with Tymlos may also increase this risk. Due to this, doctors usually avoid prescribing Tymlos for people with certain types of bone disease, including Paget’s disease. Your doctor can provide more information on whether Tymlos is safe for you.

High calcium level in your blood or urine. Tymlos can cause hypercalcemia (a high calcium level in your blood) or hypercalciuria (a high calcium level in your urine) as a side effect. If you already have either of these conditions, your doctor will likely delay your treatment with Tymlos and treat your high calcium level first.

High parathyroid hormone level. Tymlos can cause a high calcium level in your blood as a side effect. Having hyperparathyroidism (a high parathyroid hormone level) can increase your risk of this side effect from Tymlos. If you have hyperparathyroidism, your doctor will likely want to manage this condition first before prescribing Tymlos for you.

Current or past kidney stone. It’s not known whether it’s safe to use Tymlos if you have or have had a kidney stone. This drug can cause a high level of calcium in your urine, which can cause or worsen kidney stones. Your doctor can help determine whether Tymlos is safe for you to take.

Allergic reaction. If you’ve had an allergic reaction to Tymlos or any of its ingredients, your doctor will likely not prescribe it for you. Ask them about other medications that might be better options.

Alcohol and Tymlos

There are no known interactions between alcohol and Tymlos, but both can cause some similar side effects. Examples include fatigue, nausea, and headache. Combining the two can increase your risk of these side effects.

In addition, heavy alcohol consumption may also weaken your bones. (Tymlos is prescribed to treat osteoporosis, or weak bones, in certain adults.)

For these reasons, your doctor may suggest moderating or avoiding alcohol consumption if you drink alcohol, have osteoporosis, and are prescribed Tymlos.

Pregnancy and breastfeeding with Tymlos

Tymlos isn’t approved for use in people who can become pregnant. (It’s prescribed for use only in postmenopausal females and certain males.*) Because of this, the drug hasn’t been studied in pregnant or breastfeeding people, so it’s not known whether it’s safe to use in these situations.

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

Like most drugs, Tymlos can cause side effects. For most people, these are mild and go away on their own. In rare instances, though, Tymlos can cause serious side effects.

If you have questions about side effects that Tymlos can cause, talk with your doctor. Examples of questions to help get you started include:

  • Do any of the medications I take interact with Tymlos and increase my risk of side effects?
  • Does my risk of side effects depend on the dosage I’m prescribed?
  • How do side effects of Tymlos compare with those of other drugs used to treat osteoporosis, such as Fosamax?

To learn more about Tymlos, 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.

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.