Like other medications, taking omalizumab (Xolair) may come with side effects. Some are mild, while others can be serious. When you know what to look for, you’ll know how to respond if you have any side effects.
Omalizumab is approved to treat:
- Allergic asthma
- Chronic hives (chronic idiopathic urticaria)
- Nasal polyps
How to Manage Common Side Effects of Omalizumab (Xolair)
Some people have side effects that are common. They may go away as your body gets used to the medicine. If they are severe or continue, call your doctor right away.
These are a few of the common side effects:
Fatigue. You may feel tired after you get your injection. This side effect was reported in some people over the age of 12 who took omalizumab for asthma. In some cases, it fades away quickly.
If the fatigue feels unusual or overwhelming, you should tell your doctor right away.
To try to ease the tiredness, you can:
- Keep a regular sleep schedule
- Exercise
- Eat a healthy diet
- Avoid alcohol, nicotine, and illegal drugs
- Do things that reduce your stress, like yoga, meditation, or a walk
- Stay hydrated
Muscle or joint aches. These are common in people taking omalizumab who have:
- Asthma and are over the age of 12
- Nasal polyps
- Chronic hives
To handle this, you can try:
- Oral pain-relieving medications like acetaminophen (Tylenol) or a nonsteroidal anti-inflammatory drugs (NSAIDS) like ibuprofen
- Topical medicines such as creams, patches, sprays, and ointments like capsaicin, menthol, and camphor
- Hot or cold therapy, acupuncture, and rest
- Good nutrition and exercise
- Relaxation techniques and deep breathing
Injection site reaction. It’s not uncommon for your skin to be sore where the needle went in. The needle may cause it, the medicine may cause it, or it can be a combination of the two. Your skin may look red or be swollen. It can also be itchy or painful. People getting omalizumab for nasal polyps reported this side effect.
You can treat a reaction at the injection site with:
- Over-the-counter pain medicines
- Ice
- Prescription medicines if there’s an infection
Tell your doctor if you have:
- A fever over 100.4 F
- Muscle aches
- Serious pain where you got the shot
- Blistering
- Nausea
- Headache
- Dizziness
- Worsening symptoms
You may be able to prevent an injection site reaction if the person who gives you the shot inserts the needle correctly. If you do it yourself, ask for tips from your health care provider.
Other things that can help may include making sure the medicine is room temperature before injection, using breathing exercises, and using the right kind of syringe.
Stomach pain. You may have pain in your upper abdomen after you take omalizumab. This is common in children between the ages of 6 and 12 who took omalizumab. People taking omalizumab for nasal polyps also reported belly pain.
It’s not clear what exactly causes this. Your abdomen includes several organs, so pain in this area may not necessarily be from your stomach.
To ease stomach pain, you can:
- Eat bland foods that are easy to digest such as bananas and crackers
- Apply heat or take a warm bath
- Drink water
- Try home remedies like ginger for indigestion or peppermint to relax muscles
See your doctor right away if you have:
- Bad pain or pain that doesn’t stop or gets worse
- Blood in your vomit or stool
- Appetite loss
- Pain while swallowing
- Diarrhea for more than 2 days
- Nighttime diarrhea that prevents you from sleeping
- Weight loss
Headache. This was reported in some people taking omalizumab who have:
- Asthma and are between ages 6 and 12
- Nasal polyps
- Chronic hives
Depending on how bad they are, you can treat headaches with:
- Pain medicines like acetaminophen or ibuprofen (but avoid giving aspirin to children and teenagers because it is linked to Reye’s syndrome)
- Biofeedback
- Massage
- Acupuncture
- Cognitive behavioral therapy (CBT)
Get immediate medical help for a headache that is severe, comes on suddenly, or comes with any neck pain, fever, weakness, numbness, confusion, or trouble seeing or speaking, or if you have had any type of head injury.
You may be able to prevent a headache when you get your injection. In a published case study, a young child took acetaminophen 1 hour before the injection, which kept the pain from starting.
Skin rash and itching. Some adults and children older than 12 with asthma reported this when taking omalizumab. It could be from a wide range of causes. It may be an injection-site reaction or allergic reaction. Ask your doctor about it so they can tell what type of skin rash it may be.
To treat a skin rash, your doctor may suggest:
- Creams to ease inflammation and itching (cortisone)
- Allergy medicines, including antihistamines
- Steroids (prednisone)
- Oatmeal baths
Dizziness. This can be from the medication or from a lot of other conditions. In studies, people who had it were:
- 12 years older with asthma
- Adults with nasal polyps
Your doctor may treat this differently based on what causes it. If it’s from the medicine, they may ask you to limit your activity while your body adjusts. If it’s from another cause like an inner ear infection, they may treat the infection.
Talk to your doctor if it is severe or if it continues.
Bone fractures. Some children over 12 and adults with allergic asthma reported this common injury while they were taking omalizumab. It’s not clear how it is related to the medication.
If you think you have a bone fracture, see your doctor. Symptoms include:
- Swelling
- Pain
- Bruising
- Not being able to move the area like usual
- A bump
Treatment may include having the bones reset, a splint, or a cast. It may need surgery depending on the case.
To prevent a bone fracture:
- Prioritize safety – wear your seatbelt in the car, don’t stand on unstable surfaces, keep your space free from clutter, use a cane or walker if needed.
- Follow an eating plan that promotes bone health.
- Get a bone density test if you’re over 50 or if osteoporosis runs in your family.
Ear pain or infection. Some children between ages 6 and 12 with asthma reported ear infections when taking omalizumab. Not all ear pain is caused by infection.
Your doctor may suggested treating this with:
- Oral pain medicines such as acetaminophen or ibuprofen
- Pain-relieving ear drops
- Antibiotics, if your doctor believes there is an infection
- Ear tubes, which are used for chronic cases
A few ways you may be able to prevent ear infections in children:
- Manage allergies.
- Try to prevent colds by making sure kids wash their hands; don’t share food, cups, or utensils; and cover their mouths and noses when they sneeze.
- Breastfeed babies.
- Bottle-feed babies in an upright position.
- Stay up-to-date on vaccines.
- Report mouth-breathing to your doctor, which could be a sign of large adenoids that may bring on ear infections.
Upper respiratory infections. Some people with chronic hives say they got a cold while taking omalizumab. Upper respiratory infections last 1 or 2 weeks and usually go away without treatment.
Usually viruses cause them, so antibiotics won’t help. Some ways to treat the infections include:
- Pain relievers
- Stay hydrated
- Rest
To prevent one:
- Wash your hands.
- Avoid contact with others who are sick.
- Drink a lot of water.
- Stop smoking.
- Get enough sleep.
Nasal symptoms. In clinical studies, some people with chronic hives and kids ages 6 to 12 with asthma reported swelling in the nose, throat, or sinuses. That can be a sinus infection.
To treat swelling in the nasal area, you can:
- Use saline spray.
- Take decongestants or nasal corticosteroids if your doctor suggests them.
- Try allergy medications or immunotherapy, if allergies cause it.
- Take over-the-counter pain relievers.
- Get antibiotics if it turns into a bacterial infection and your doctor says you need them.
- Drink plenty of water.
- Rest.
- Put a warm compress over your sinuses.
- Breathe in steam.
- Rinse your sinuses.
To try and prevent swelling in the nasal area:
- Rinse your nasal passages or use saline spray.
- Inhale steam.
- Avoid air that’s too dry.
- Keep your head elevated while sleeping.
- Stay hydrated.
- Limit decongestants.
- Avoid antihistamines unless needed.
- Be gentle when you blow your nose.
- Avoid smoke.
- Wash your hands regularly.
- Stay up-to-date on vaccines.
Swelling in your throat can be a sign of a life-threatening allergic reaction. Call 911 if it happens.
Nosebleeds. In clinical studies, kids ages 6 to 12 with asthma reported nosebleeds while taking omalizumab. Most of these can be handled at home.
To treat a nosebleed:
- Lean your body and head forward so blood doesn’t go down your throat.
- Apply pressure to the soft part of the nose with your fingers for about 5 minutes. Check to see if it’s still bleeding. Go back to squeezing for another 10 minutes if it doesn’t stop.
Reach out for medical care if the bleeding doesn’t stop after 20 minutes of direct pressure.
You may be able to prevent nosebleeds with:
- Saline spray, nasal gel, or ointment
- A cool-mist humidifier at night
Nausea. Some people with chronic hives reported nausea while taking omalizumab.
To get relief from nausea, you can:
- Drink cold, clear liquids.
- Eat small amounts of bland foods.
- Don’t brush your teeth after eating.
- Avoid mixing hot and cold foods.
- Try not to move too much after eating.
- Take an over-the-counter medicine like antacids.
- Avoid strong odors.
After the drug came out, official postmarketing data shows people also reported:
- Hair loss
- Low platelet count
What to Do If You Have Serious Side Effects From Omalizumab (Xolair)
Some side effects from omalizumab may be serious or life-threatening. When you know what they are, you’ll know what to do if you experience them.
Seek emergency care if you have any of these serious side effects:
Severe allergic reaction/anaphylaxis. Swelling, hives, itching, or shortness of breath can indicate a severe allergic reaction called anaphylaxis. Call 911 immediately if you have any of these symptoms. Some people get this after getting the shot, even if they didn’t have it with previous injections.
Shortness of breath. This could mean you have anaphylaxis, an asthma attack, or another issue. Call 911 for any shortness of breath.
Doing these things may help you prevent shortness of breath:
- Don’t smoke.
- Avoid fumes, smoke, and other pollutants.
- Stay out of extreme temperatures.
- Maintain a healthy weight.
- Take any medications as prescribed.
- Give yourself time to adjust if you travel to a higher altitude.
- Exercise regularly.
Fever, rash, muscle aches, or swollen glands within a few days of injection. This cluster of symptoms was reported in some people taking omalizumab within 1 to 5 days of getting their shot. Your doctor can tell if they think these symptoms are from the medicine or something else.
Blood vessel inflammation. This is rare but can happen if you have asthma and take omalizumab. It’s more likely if you stop taking an oral steroid or lower the dose. Experts don’t know if the inflammation is from taking omalizumab.
Symptoms may include:
- Rash
- Chest pain
- Shortness of breath
- Tingling or numbness in your arms or legs
Get emergency medical help for any chest pain, shortness of breath, or numbness or tingling.
Parasitic infection. This can happen if you’re exposed to parasites like roundworm or hookworm. If you are at a high risk for exposure to these parasites, your doctor can test your stool to confirm if you have this infection and give you medication to treat it.
Cancer. Some people who were taking omalizumab reported getting cancer. But there’s not enough evidence to show that the drug causes cancer.
Heart and circulation issues. Some people on omalizumab have had these side effects:
- Chest pain
- Weakness on one side of the body
- Heart attack
- Blood clots in the lungs or legs
- Slurred speech
- Vision changes
Call 911 if you have any of these symptoms as they can be the signs of a stroke or heart attack. Experts don’t know if these are directly caused by the medicine.
