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Natalizumab Side Effects

For the Consumer

Applies to natalizumab: intravenous solution

Along with its needed effects, natalizumab 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 or nurse immediately if any of the following side effects occur while taking natalizumab:

More common
  • Body produces substance that can bind to drug making it less effective or cause side effects
  • cough
  • difficulty with swallowing
  • dizziness
  • fast heartbeat
  • hives, itching, skin rash
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • tightness in the chest
  • unusual tiredness or weakness
  • Blurred vision
  • changes in behavior
  • chest pain
  • confusion
  • difficult or labored breathing
  • faintness or lightheadedness when getting up suddenly from a lying or sitting position
  • feeling of warmth
  • feeling unusually cold
  • fever
  • gaseous abdominal or stomach pain
  • nausea
  • redness of the face, neck, arms, and occasionally, upper chest
  • shivering
  • sneezing
  • sore throat
  • stomach fullness
  • sweating
  • thoughts of killing oneself
  • yellow eyes or skin
Incidence not known

Some side effects of natalizumab 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
  • Bladder pain
  • blistering, crusting, irritation, itching, or reddening of the skin
  • bloody or cloudy urine
  • cracked, dry, scaly skin
  • diarrhea
  • difficult, burning, or painful urination
  • difficulty with moving
  • discouragement
  • feeling sad or empty
  • frequent, strong, or increased urge to urinate
  • irregular menstruation
  • irritability
  • itching of the vagina or genital area
  • loss of interest or pleasure
  • lower back or side pain
  • muscle pain or stiffness
  • pain during sexual intercourse
  • pain in the joints
  • pain, cramps, or heavy bleeding
  • passing urine more often
  • stomach soreness or discomfort
  • swollen glands
  • thick, white vaginal discharge with no odor or with a mild odor
  • trouble concentrating
  • trouble sleeping
Less common
  • Absent, missed, or irregular menstrual periods
  • chest discomfort
  • fainting
  • local bleeding
  • shakiness in the legs, arms, hands, or feet
  • stopping of menstrual bleeding
  • trembling or shaking of the hands or feet

For Healthcare Professionals

Applies to natalizumab: intravenous concentrate


Frequency not reported: Acute retinal necrosis (ARN), blindness, decreased visual acuity, redness, eye pain[Ref]

Nervous system

Very common (10% or more): Headache (38%)
Common (1% to 10%): Vertigo, somnolence, tremor, dizziness
Uncommon (0.1% to 1%): Progressive multifocal leukoencephalopathy (PML)
Frequency not reported: Tremor[Ref]


Very common (10% or more): Upper respiratory tract infection (22%), lower respiratory tract infection (17%)
Common (1% to 10%): Pharyngolaryngeal pain, cough, sinusitis, nasopharyngitis[Ref]


Very common (10% or more): Depression (19%)[Ref]


Very common (10% or more): Nausea (17%), gastroenteritis (11%), abdominal discomfort (11%), diarrhea (10%)
Common (1% to 10%): Dyspepsia, constipation, flatulence, aphthous stomatitis, tooth infection, tonsillitis
Frequency not reported: Vomiting[Ref]


Very common (10% or more): Influenza-like illness (12%)
Common (1% to 10%): Herpes, tonsillitis, viral infection, immunogenicity[Ref]


Common (1% to 10%): Abnormal liver function test
Postmarketing reports: Serious liver injuries, increased liver enzymes, hyperbilirubinemia[Ref]


Very common (10% or more): Fatigue (27%)
Common (1% to 10%): Tooth infections, toothache, rigors
Frequency not reported: Flushing, feeling cold, pyrexia[Ref]


Frequency not reported: Localized hypersensitivity reactions[Ref]


Very common (10% or more): Urinary tract infection (21%), vaginitis (10%)
Common (1% to 10%): Irregular menstruation, dysmenorrhea, amenorrhea, ovarian cyst, urinary incontinence, urinary urgency/frequency[Ref]


Very common (10% or more): Arthralgia (19%), pain in extremity (16%), back pain (12%)
Common (1% to 10%): Rigors, muscle cramp, joint swelling[Ref]


Very common (10% or more): Rash (12%)
Common (1% to 10%): Dermatitis, pruritus, night sweats, dry skin, urticaria[Ref]


Common (1% to 10%): Immediate or delayed hypersensitivity reactions, seasonal allergy
Frequency not reported: anaphylaxis/anaphylactoid reaction[Ref]


Rare (less than 0.1%): Anemia, hemolytic anemia[Ref]


Common (1% to 10%): Weight increased, weight decreased, peripheral edema[Ref]


Common (1% to 10%): Chest discomfort[Ref]


1. Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. Available from: URL:" ([2006]):

2. "Product Information. Tysabri (natalizumab)." Elan Pharmaceutical/Athena Neurosciences Inc, South San Francisco, CA.

3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

Some side effects of natalizumab may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.