10 Ocrevus Side Effects: What to Expect When Starting Infusions for Multiple Sclerosis

If you’re living with multiple sclerosis (MS), one treatment option your prescriber may consider is Ocrevus (ocrelizumab). Ocrevus is an infused B-cell therapy that treats two different types of MS in adults — primary progressive (PPMS) and relapsing forms.

One benefit of Ocrevus is that, after the first two doses, you only need to receive it twice a year. However, each intravenous (IV) infusion lasts for several hours. This is because your healthcare team may need to slow down your infusion due to side effects. They also need to monitor you for potential reactions afterward. So, what can you expect when starting Ocrevus? 

Ocrevus side effects at a glance

Ocrevus can cause both mild and more serious side effects. Your healthcare team will monitor you for side effects during the infusion and for a period of time after. But some side effects can also happen after you leave your infusion site.

Common Ocrevus side effects include:

• Infections (e.g., common cold, skin infections)

• Cough

• Infusion reactions

• Depression

• Back pain

• Diarrhea

• Swelling in your arms and legs

Less common but potentially serious Ocrevus side effects include:

• Serious allergic reactions (anaphylaxis)

• Inflamed colon (colitis)

• Progressive multifocal leukoencephalopathy (PML)

• Increased risk of cancer, including breast cancer

Let’s review 10 possible Ocrevus side effects in more detail below.

1. Infections

Infections are a common Ocrevus side effect. This is because Ocrevus kills some of your immune cells, which can put you at a higher risk of getting infections. These can include:

• Upper respiratory tract infections (e.g., sinus infections, pharyngitis)

• Lower respiratory tract infections (e.g., bronchitis)

• Herpes infections

• Hepatitis B reactivation

Some signs you might have an infection include fever, chills, or a constant cough. You might also notice sores on your mouth or genitals, eye pain, or pain while urinating. If you experience any of these symptoms, contact your prescriber. They’ll want to check to see if you have an infection and get you the right treatment.

Before starting Ocrevus, it’s a good idea to make sure you’re all caught up with your vaccines. In fact, you’ll be screened for certain vaccine-preventable illnesses, such as hepatitis B, before receiving Ocrevus to make sure it’s safe. Get any live vaccines, such as a measles, mumps, and rubella (MMR) vaccine, at least 4 weeks before you start Ocrevus. Other vaccines should be administered at least 2 weeks before.

Good to know: Tell your healthcare team before your Ocrevus appointment if you’re sick. Ocrevus can make it harder to fight off an existing infection, so they’ll reschedule your infusion for after you’ve recovered.

2. Infusion reactions

Ocrevus can commonly cause infusion reactions. These are most likely to happen during your first infusion but can happen after any dose. Symptoms of an infusion reaction might include:

• Itching

• Rash

• Red skin

• Tightening of your airways

• Mouth or throat pain

• Shortness of breath

• Fever

• Headache

• Dizziness

• Nausea

Infusion reactions from Ocrevus can range from mild to severe. In mild-to-moderate cases, your healthcare team will typically slow down how quickly your dose is infused. But in severe cases, they may need to temporarily stop your infusion to allow you to recover before starting it again. In the event of a life-threatening reaction, the infusion will be stopped and you’ll receive supportive care right away.

To lower your risk for an infusion reaction, your healthcare team will give you medications before your infusion. These might include a steroid (such as methylprednisolone), an antihistamine, and an anti-fever medication such as acetaminophen (Tylenol). You’ll also be monitored for at least 1 hour after each infusion to make sure you’re not having a bad reaction.

3. Depression

You might experience depression during Ocrevus treatment. Keep in mind that depression is common in people living with MS, so it may or may not be a side effect of your medication. In fact, it’s estimated that 1 in 3 people with MS have depression.

If you have symptoms of depression, there are many resources available to help. One example is finding an MS support group to connect with people going through a similar experience. Talk with your care team if you or a loved one notices mood changes or worsening depression.

4. Back pain

Some people experience back pain after receiving Ocrevus. However, back pain is a common problem from having MS. So, it may not be clear if your back pain is due to your medical condition or the medication. 

No matter the cause, back pain can typically be managed at home. A hot or cold pack or over-the-counter (OTC) pain remedies may help. Be sure to contact your prescriber if you experience severe back pain or back pain that doesn’t seem to be getting better.

5. Skin infections

As mentioned above, infections are a common Ocrevus side effect. These include skin infections. In clinical studies of adults receiving Ocrevus for PPMS, 14% reported a skin infection.

Skin infections can have many causes. Some signs of a skin infection include a rash, pain, or itching. It’s also possible to get a fever from skin infections. See your prescriber if you think you might have a skin infection so you can get appropriate treatment if needed.

6. Diarrhea

Diarrhea is also possible with Ocrevus. In most cases, it should resolve on its own. But in rare instances, the diarrhea may be from colon inflammation, which requires medical attention. It’s also possible that the underlying MS could be causing the diarrhea, too.

For mild diarrhea, you can try avoiding food triggers, such as dairy and greasy foods. There are also OTC treatments such as loperamide (Imodium) for symptom relief. It’s also a good idea to keep hydrated to replace fluids lost from diarrhea.

But if you have diarrhea that’s persistent or happening with symptoms such as abdominal pain and black or bloody stool, tell your prescriber right away.

7. Swelling in the extremities

Some people receiving Ocrevus for PPMS experienced swelling in their arms and legs during clinical trials. This could be due to the extra fluid you’re getting from the infusion. But it could also be due to MS or other medications, too. 

If you notice that you have puffy legs or arms, speak to your healthcare team to find out the cause. Take note of when the swelling started and if anything makes it worse. To alleviate swollen feet or ankles at home, it may help to keep your feet elevated for periods of time or wear compression socks.

8. Inflamed colon (colitis)

As mentioned above, there have been rare instances where Ocrevus has been linked to immune-mediated colitis (inflammation of the colon). While this wasn’t reported during clinical studies, some people experienced colitis after Ocrevus came on the market. Severe cases may need to be treated in the hospital.

Colitis can happen within a few weeks to years of starting Ocrevus. Watch out for symptoms of colitis, such as persistent diarrhea, stomach pain, and bloody stools. Contact your prescriber if these develop, but go to the nearest ER if they’re severe.

9. Progressive multifocal leukoencephalopathy

Another serious but rare Ocrevus side effect is progressive multifocal leukoencephalopathy (PML). PML is a serious viral infection in the brain that typically happens in people with weakened immune systems. Some symptoms of PML include:

• Weakness on one side of the body

• Clumsiness

• Vision changes

• Problems with thinking or memory

• Personality changes

If you notice any of the symptoms listed above, seek medical attention right away. If left untreated, PML can lead to permanent disability or death.

10. Increased risk of cancer

While uncommon, there were more cancer cases, including breast cancer, in people receiving Ocrevus during clinical trials. This was compared with people taking Rebif (interferon beta-1a) or a placebo.

It’s not clear if Ocrevus raises the risk for cancer by itself, or if it’s due to other reasons — such as other previous medications that you may have taken. Your healthcare team can discuss this risk with you and advise you on recommended self-exams or screenings.

When should you contact your prescriber about Ocrevus side effects?

Don’t hesitate to reach out to your healthcare team if you’re having bothersome side effects. Many side effects from Ocrevus can be managed with proper treatment. But it’s important to know when you should seek medical attention. 

If you have any of the following symptoms, it’s best to contact your prescriber:

• Signs of infection (e.g., fever, chills, persistent cough)

• Signs of an infusion reaction (itching, nausea, dizziness)

• Worsening depression

• Diarrhea that occurs with stomach pain or black or bloody stools

• Weakness on one side of the body

• Vision changes

Why trust our experts?

Written by:

Kristianne Hannemann, PharmD

Kristianne Hannemann, PharmD, is a licensed pharmacist in California. She has been a retail pharmacy manager and staff pharmacist for over 7 years and has contributed drug information content to different health companies.

Edited by:

Alyssa Billingsley, PharmD

Alyssa Billingsley, PharmD, is the director of pharmacy content for GoodRx. She has over a decade of experience as a pharmacist and has worked in clinical, academic, and administrative roles.

Reviewed by:

Austin Ulrich, PharmD, BCACP

Austin Ulrich, PharmD, BCACP, is a board-certified ambulatory care clinical pharmacist. In his early career, he provided direct patient care in a variety of settings, including hospital and community pharmacies, and in a primary care clinic as a clinical pharmacist.

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