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Tyruko (Intravenous)

Generic name: natalizumab-sztn

Last updated July 11, 2026 0 views
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Uses for Tyruko

Natalizumab-sztn injection is used to treat the relapsing forms of multiple sclerosis (MS), which include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease. This medicine will not cure MS, but it may help slow down some of the disabling effects and reduce the number of relapses.

Natalizumab-sztn injection is also used to treat moderate to severe Crohn's disease (CD) when other medicines or treatments have not worked well. This medicine will not cure CD, but it may help prevent it from happening again.

This medicine is available only through a restricted distribution program called the Tyruko® REMS (Risk Evaluation and Mitigation Strategy) Program.

This section was rewritten for readability and reviewed for meaning.

Precautions while using Tyruko

Your doctor will want to check how you are doing at 3 months and 6 months after your first injection, and then every 6 months after that. You may need blood and urine tests to look for unwanted side effects.

This medicine may increase your risk of getting infections, including a rare and serious brain infection called progressive multifocal leukoencephalopathy (PML). The risk is higher if you have had a JCV infection, have been on natalizumab-sztn for more than 2 years, or have taken medicine that weakens your immune system (like azathioprine, cyclophosphamide, cyclosporine, mercaptopurine, methotrexate, mitoxantrone, mycophenolate mofetil, or steroid medicine) before starting this medicine. Contact your doctor right away if you notice changes in your vision, loss of coordination, clumsiness, memory loss, difficulty speaking or understanding others, or weakness in your legs.

This medicine may lead to a rare condition called immune reconstitution inflammatory syndrome (IRIS). This can happen after stopping the medicine if you had PML during treatment. Notify your doctor immediately if you have an inflammatory reaction to an infection that includes mild burning, stinging, or tingling of the skin, or a feeling of heat, redness, or swelling of the skin.

Natalizumab-sztn may increase the risk of developing encephalitis, meningitis, or acute retinal necrosis caused by herpes and varicella viruses. Contact your doctor if you have a fever, headache, eye pain or redness, sensitivity of the eyes to sunlight, or confusion.

Get in touch with your doctor immediately if you experience pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, vomiting, or yellowing of the eyes or skin. These could be signs of a serious liver issue.

This medicine may cause serious allergic reactions, including anaphylaxis, which can be life-threatening and requires immediate medical help. Inform your doctor right away if you develop a rash, itching, hoarseness, trouble breathing or swallowing, or any swelling of your hands, face, or mouth after taking this medicine.

This medicine may reduce the number of certain types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help prevent these issues, avoid close contact with sick people or those with infections. Wash your hands frequently. Stay away from rough sports or activities where you could get bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.

Make sure any doctor or dentist treating you knows that you are using this medicine.

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Before using Tyruko

In deciding to use a medicine, it's important to consider the risks against the benefits. This is a decision you and your doctor will make together. For this medicine, you should think about the following:

Allergies

Inform your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also, let your healthcare professional know if you have any other allergies, such as to foods, dyes, preservatives, or animals. For over-the-counter products, read the label or package ingredients carefully.

Pediatric

There have not been appropriate studies on how age affects the use of natalizumab-sztn injection in children. Safety and effectiveness have not been established.

Geriatric

Current studies have not shown any specific problems in elderly patients that would limit the usefulness of natalizumab-sztn injection.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medicine while breastfeeding. Weigh the potential benefits against the potential risks before using this medicine during breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while others may be used together even if an interaction might occur. In these cases, your doctor may adjust the dose or take other precautions. When receiving this medicine, it is especially important for your healthcare professional to know if you are taking any of the medicines listed below. The following interactions have been chosen based on their potential significance and are not necessarily a complete list.

Using this medicine with any of the following medicines is usually not recommended but may be necessary in some cases. If both medicines are prescribed together, your doctor may change the dose or frequency of one or both medicines.

  • Anifrolumab-fnia
  • Infliximab
  • Vedolizumab

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be taken at or around the time of eating food or certain types of food due to potential interactions. Using alcohol or tobacco with certain medicines may also lead to interactions. Discuss the use of your medicine with food, alcohol, or tobacco with your healthcare professional.

Other Medical Problems

Having other medical problems may impact the use of this medicine. Ensure you tell your doctor if you have any other medical issues, especially:

  • Herpes infection—Use with caution. May increase the risk for more serious infections (e.g., encephalitis, meningitis, retinal necrosis).
  • Liver disease—Use with caution. This medicine may worsen this condition.
  • Progressive multifocal leukoencephalopathy (PML, a rare brain infection) or a history of it—Should not be used in patients with this condition.
  • Weak immune system (due to HIV infection, AIDS, leukemia, lymphoma, or organ transplant)—Use is not recommended. May increase the risk of developing infections, including PML.

This section was rewritten for readability and reviewed for meaning.

Side Effects of Tyruko

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may happen, if they do, they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur:

More common

  • Bladder pain
  • bloating or swelling of the face, arms, hands, lower legs, or feet
  • bloody or cloudy urine
  • burning or stinging of the skin
  • chest tightness
  • chills
  • cough
  • diarrhea
  • difficult, burning, or painful urination
  • difficulty in breathing or swallowing
  • discouragement
  • dizziness or lightheadedness
  • facial swelling
  • fast heartbeat
  • feeling of constant movement of self or surroundings
  • feeling sad or empty
  • fever
  • frequent urge to urinate
  • headache
  • irritability
  • itching of the vagina or genital area
  • loss of appetite
  • loss of interest or pleasure
  • lower back or side pain
  • nausea
  • pain during sexual intercourse
  • pain or tenderness around eyes and cheekbones
  • painful cold sores or blisters on the lips, nose, eyes, or genitals
  • rapid weight gain
  • sensation of spinning
  • skin itching, rash, or redness
  • sneezing
  • sore throat
  • stomach pain
  • stuffy or runny nose
  • swelling of the face, throat, or tongue
  • thick, white vaginal discharge with no odor or with a mild odor
  • tingling of the hands or feet
  • trouble concentrating
  • trouble sleeping
  • unusual tiredness or weakness
  • unusual weight gain or loss
  • vomiting

Less common

  • Bloating
  • loss of bladder control
  • sleepiness or unusual drowsiness
  • stomach or pelvic discomfort, aching, or heaviness

Incidence not known

  • Back, leg, or stomach pains
  • black, tarry stools
  • bleeding gums
  • blood in the urine or stools
  • blurred vision
  • chest pain
  • confusion
  • dark urine
  • feeling of heat, redness, or swelling of the skin
  • general body swelling
  • general feeling of illness
  • mild burning, stinging, or tingling of the skin
  • nosebleeds
  • pale skin
  • pinpoint red spots on the skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • seizures
  • stiff neck or back
  • unusual bleeding or bruising
  • yellow eyes or skin

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
  • blistering, crusting, irritation, itching, or reddening of the skin
  • bloated
  • chest discomfort
  • constipation
  • cracked, dry, or scaly skin
  • excess air or gas in the stomach or intestines
  • full feeling
  • heartburn
  • indigestion
  • irregular menstrual periods
  • muscle cramps
  • pain in the arms or legs
  • passing gas
  • stomach discomfort or upset
  • swelling or inflammation of the mouth

Less common

  • Feeling unusually cold
  • heavy bleeding
  • joint swelling
  • night sweats
  • shivering
  • tearing of the skin
  • trembling or shaking of the legs, arms, hands, or feet

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.

In the U.S.

  • Tyruko

Pharmacologic Class: Natalizumab

Find detailed information on biosimilars for this medication.

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Proper use of Tyruko

A nurse or other trained health professional will give you this medicine in a medical facility. It is given through a needle placed into one of your veins. The medicine must be injected slowly, so the needle will have to remain in place for about an hour every 4 weeks.

It is very important that you understand the requirements of the Tyruko® REMS program, and become familiar with the Tyruko® medication guide. Read and follow these instructions carefully. Ask your doctor if you have any questions. Ask your pharmacist for the medication guide if you do not have one.

Your doctor may need to check your brain before you start receiving this medicine. To do this, you may need to have a Magnetic Resonance Imaging (MRI) scan.

Frequently asked questions

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Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
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Content is provided for education and is not medical advice. See our medical disclaimer.