Key takeaways

  • Nplate is a prescription medication used to increase platelet count in the blood.
  • The drug can cause side effects such as dizziness, joint and muscle pain, blood clots, and allergic reactions.
  • A healthcare professional will give you Nplate as an injection under your skin.

Nplate is a prescription drug that’s used in adults and some children with immune thrombocytopenia (ITP) that hasn’t improved with other treatments.

With ITP, you have a low level of platelets that’s caused by activity of your immune system. (Platelets help your blood to form clots.) This condition used to be called idiopathic thrombocytopenic purpura.

Nplate is also prescribed for adults and children who were exposed to levels of radiation that affected their bone marrow. (Your platelets are made in your bone marrow.)

To learn more about what Nplate is used for, see the “Is Nplate used for ITP?” and “Is Nplate used for other conditions?” sections.

Nplate basics

Nplate contains the active ingredient romiplostim. (An active ingredient is what makes a drug work.) The drug is a biologic medication. Biologics are made from parts of living organisms.

Nplate is not available in a biosimilar form. (Biosimilars are like generic drugs. But unlike generics, which are made for nonbiologic drugs, biosimilars are made for biologic drugs.) Instead, romiplostim is available only as the brand-name drug Nplate.

Like most drugs, Nplate may cause mild or serious side effects. The following lists describe some of the more common side effects that Nplate may cause. These lists don’t include all possible side effects.

Keep in mind that side effects of a drug can depend on:

  • your age
  • other health conditions you have
  • other medications you may be taking

Your doctor or pharmacist can tell you more about the potential side effects of Nplate and suggest ways to help reduce side effects.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medications safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect while receiving Nplate and want to tell the FDA about it, visit MedWatch or call 800-332-1088.

Mild side effects

Here’s a short list of some of the mild side effects that Nplate can cause. To learn about other mild side effects, talk with your doctor or pharmacist, or read Nplate’s prescribing information.

Mild side effects of Nplate that have been reported include:

  • dizziness
  • pain in your joints and muscles
  • trouble sleeping
  • abdominal pain
  • upset stomach
  • tingling, burning, or numbness of your skin

For more information on dizziness and pain in your joints and muscles, see the “Side effect focus” section.

Children may have different side effects from Nplate compared with adults. Side effects seen in children may include:

  • nose or throat infection
  • mouth and throat pain
  • bruising

Mild side effects of Nplate may go away within a few days to a couple of weeks. But if they become bothersome, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from Nplate can occur, but they aren’t common. If you have serious side effects from Nplate, call your doctor right away. However, if you think you’re having a medical emergency, you should call 911 or your local emergency number.

Serious side effects of Nplate that have been reported include:

  • blood clots, which may lead to heart attack or stroke
  • loss of response to Nplate, which can lead to severe thrombocytopenia (very low platelet level)
  • bone marrow problems
  • allergic reaction, which is described next in “Side effect focus”

For more information on blood clots and loss of response to Nplate, see “Warnings” in the “What should be considered before receiving Nplate?” section. For more information on allergic reaction, see the “Side effect focus” section.

Side effect focus

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

Long-term side effects

If you’re receiving Nplate for immune thrombocytopenia (ITP), you may have to use it long term. (With ITP, you have a low level of platelets that’s caused by activity of your immune system.)

A 2016 review of studies suggests that Nplate is safe to use long term. The studies suggest that there wasn’t a significant increase in bone marrow and blood clotting issues in people receiving the drug long term.

What might help

If you need to use Nplate over a long period of time and you’re concerned about long-term side effects, talk with your doctor or pharmacist. They can discuss with you the risks and benefits of Nplate treatment.

Pain in your joints and muscles

In studies, some people had joint and muscle pain with Nplate treatment. In fact, these were common side effects of the drug.

Most of the time, these side effects were mild to moderate. And they didn’t worsen over time.

What might help

If you have pain in your joints or muscles while you’re using Nplate, talk with your doctor. They may recommend over-the-counter pain relievers and home remedies, if needed.

Feeling dizzy

You might feel dizzy during Nplate treatment.

When receiving Nplate, notice when your dizziness occurs and how long it lasts. You must avoid driving or operating machines if you feel dizzy.

What might help

If dizziness is affecting your daily activities, tell your doctor about it. They may suggest ways to help manage your dizziness.

Allergic reaction

Some people may have an allergic reaction to Nplate.

Symptoms of a mild allergic reaction can include:

  • skin rash
  • itchiness
  • flushing (warmth, swelling, or redness, or discoloration in your skin)

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include swelling under your skin, typically in your eyelids, lips, hands, or feet. They can also include swelling of your tongue, mouth, or throat, which can cause trouble breathing.

If you have an allergic reaction to Nplate, tell your doctor right away. But if you think you’re having a medical emergency, call your doctor immediately or call 911 or your local emergency number.

Your doctor will recommend the dosage of Nplate that’s right for you. The following text describes commonly used dosages, but the dosage you receive will be determined by your doctor.

Form and strengths

Nplate comes in a powder inside vials and is available in the following strengths:

  • 125 micrograms (mcg)
  • 250 mcg
  • 500 mcg

A healthcare professional will mix Nplate powder with sterile water to make a solution for injection.

Recommended dosages

If you’re receiving Nplate for immune thrombocytopenia (ITP), your doctor or a healthcare professional will give you Nplate injections once every week. Your first dose will be based on your body weight in kilograms (kg), which your doctor or a healthcare professional will calculate. Subsequent doses will depend on your platelet count.

If you’re receiving Nplate because you’ve been exposed to levels of radiation that may have harmed your bone marrow, only one dose of the drug is needed. But you must receive this dose immediately after being exposed to the radiation. This dose will be based on your body weight in kg.

Your doctor may adjust your dosing depending on your body’s response to Nplate. To monitor your response to Nplate, your doctor will order blood tests to check your platelet level.

For details about Nplate’s dosages, see this Nplate dosage article.

How it’s given

A healthcare professional will give Nplate to you as an injection under your skin in a doctor’s office or hospital.

Using Nplate with other drugs

You might need to use Nplate with other medications to treat ITP. Examples of possible ITP treatments include:

  • corticosteroids, such as prednisone
  • danazol
  • azathioprine (Imuran)
  • immunoglobulins (immune system proteins) such as intravenous immunoglobulin (IVIG) and anti-D immunoglobulin

For radiation affecting bone marrow, you may receive medications to help relieve symptoms. These include:

  • pain relievers
  • antiemetic (anti-nausea) drugs
  • antibiotics
  • colony-stimulating factors (which stimulate white blood cell production), such as pegfilgrastim (Neulasta)

Questions about using Nplate

Here are answers to some common questions about receiving Nplate.

  • What if I miss a dose of Nplate? If you miss a dose of Nplate, talk with your doctor as soon as you remember. They will tell you whether you should skip the missed dose or make an appointment to receive the missed dose.
  • Will I need to use Nplate long term? If you’re receiving Nplate for ITP, you may need to use the drug long term. Your doctor will check your body’s response to Nplate during treatment. If your platelet level doesn’t increase enough to prevent bleeding after you’ve received the maximum dose of Nplate for 4 weeks, your doctor may stop Nplate treatment. But if you’re receiving Nplate for radiation exposure, you’ll only receive one dose of the drug.
  • Should I receive Nplate with food? Nplate is given by an injection under your skin. Your body’s absorption of Nplate doesn’t depend on whether you’ve eaten or not. So you may receive Nplate injections on a full or empty stomach.
  • How long does Nplate take to work? Nplate starts working right away to increase your platelet level. When first starting Nplate, your doctor will check your platelet level. And they’ll continue to check your platelet level while you’re using Nplate. The results of these blood tests will help your doctor adjust your Nplate dosage if needed.
Questions for your doctor

You may have questions about Nplate and your treatment plan. It’s important to discuss all your concerns with your doctor.

Here are a few tips that might help guide your discussion:

  • Before your appointment, write down questions like:
    • How will Nplate affect my body, mood, or lifestyle?
  • Bring someone with you to your appointment if doing so will help you feel more comfortable.
  • If you don’t understand something related to your condition or treatment, ask your doctor to explain it to you.

Remember, your doctor and other healthcare professionals are available to help you. And they want you to get the best care possible. So don’t be afraid to ask questions or offer feedback on your treatment.

Costs of prescription drugs can vary depending on many factors. These factors include what your insurance plan covers and which pharmacy you use.

If you have questions about how to pay for your prescription, talk with your doctor or pharmacist. You can also visit the Nplate manufacturer’s website to see support options.

For information on how to save on your prescription, see this article on the cost of Nplate.

If you have a bleeding disorder called immune thrombocytopenia (ITP), your doctor may prescribe Nplate. This condition used to be called idiopathic thrombocytopenic purpura.

Nplate is a prescription drug used in adults and some children with ITP that hasn’t improved with other treatments. Specifically, doctors prescribe Nplate for:

  • adults with ITP that didn’t improve with any of the following ITP treatments:
  • children ages 1 year and older who’ve had ITP for at least 6 months that didn’t improve with any of the ITP therapies just listed

With ITP, you have a low level of platelets that’s caused by activity of your immune system. (Platelets help your blood to form clots.) Without enough platelets, you may bleed more easily or have trouble stopping a bleed from inside your body.

If you have ITP, you may have bruises or tiny red, purple, brown, or black dots on your skin. Sometimes you might find bruises in your mouth. Other symptoms of ITP may include:

Nplate helps your body make more platelets. It does this by attaching to certain cells in your bone marrow. Once Nplate binds to them, the cells are activated to make platelets.

In addition to treating immune thrombocytopenia (ITP), as described previously, Nplate has another use.

If you were exposed to levels of radiation that affected your bone marrow, your doctor may recommend Nplate. For this use, the drug can be given to adults and children, including newborns.

Your platelets are made in your bone marrow. If your bone marrow was harmed by radiation, you may have a low level of platelets.

Platelets help your blood to form clots. Without enough platelets, you may bleed inside your body or have trouble stopping a bleed from within.

Nplate helps your body make more platelets. It does this by attaching to certain cells in your bone marrow. Once Nplate binds to them, the cells are activated to make platelets.

Find answers to some commonly asked questions about Nplate.

How does Nplate work?

Nplate is a thrombopoietic receptor agonist (TPO-RA). Its mechanism of action (how it works) involves attaching to the TPO receptor (binding site) on a specific type of bone marrow cell. For more information, refer to this how Nplate works article.

Does Nplate cause hair loss?

No, hair loss isn’t a side effect of Nplate. If you have hair loss after starting Nplate, talk with your doctor. They can offer suggestions for how to manage it.

How does Nplate compare with Promacta?

Both Nplate and Promacta are brand-name drugs used in adults and some children with immune thrombocytopenia (ITP). With ITP, you have a low level of platelets that’s caused by activity of your immune system. Platelets help your blood to form clots.

But Nplate and Promacta also have other uses. To learn about Nplate’s uses, see the “Is Nplate used for ITP?” and “Is Nplate used for other conditions?” sections. To see Promacta’s uses, view its prescribing information.

While Nplate contains the active ingredient romiplostim, Promacta contains the active ingredient eltrombopag. (An active ingredient is what makes a drug work.) Unlike romiplostim, eltrombopag isn’t a biologic drug. (Biologics are made from parts of living organisms.)

Nplate is given as an injection under your skin by a healthcare professional. Promacta comes in forms you’ll take by mouth. Because the administration of Nplate and Promacta are different, their side effects may be different, too.

Aside from Promacta, another brand-name form of eltrombopag is Revolade. But this drug isn’t available for prescription in the United States.

If you’d like to know more about Nplate and Promacta, talk with your doctor or pharmacist.

Some important things to discuss with your doctor when considering Nplate treatment include:

  • your overall health
  • any medical conditions you may have

Tell your doctor if you’re taking other medications. This is important, as some drugs can interfere with Nplate. These and other considerations to discuss with your doctor are described here.

Interactions

Taking medications, vaccines, foods, and other things with a certain drug can affect how the drug works. These effects are called interactions.

Before receiving Nplate, be sure to tell your doctor about all medications you take, including prescription and over-the-counter types. Also describe any vitamins, herbs, or supplements you use. Your doctor or pharmacist can tell you about any interactions these items may cause with Nplate.

Interactions with drugs or supplements

So far, there aren’t any known interactions between Nplate and drugs, vitamins, herbs, or supplements. But to be safe, before taking any medication, vitamin, herb, or supplement, talk with your doctor or pharmacist.

Warnings

Nplate may not be right for you if you have certain medical conditions or other factors that affect your health. Talk with your doctor about your health history before you start Nplate treatment. Factors to consider include those listed here:

Injecting too much Nplate can cause very serious side effects. For this reason, your doctor or a healthcare professional will carefully calculate and inject your Nplate doses. Because of this, it’s unlikely that you’ll receive too much of this drug.

If you receive too much Nplate, your platelet level may rise too high and cause blood clotting. And increased blood clotting can cause stroke or heart attack.

What to do in case you receive too much Nplate

If you receive too much Nplate, your doctor will stop Nplate injections and check your platelet level.

You’ll start receiving Nplate again only when it’s safe for you to do so.

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.