If you have certain types of cancer, your doctor might suggest Avastin (bevacizumab) as a treatment option for you. So you may be looking for more information about this drug, including what side effects it can cause.

Avastin is a prescription medication that’s used in adults to treat certain forms of the following types of cancer:

Avastin is a biologic drug (a drug made using living cells). It’s a targeted therapy for cancer. This is a treatment that works precisely on specific proteins that help cancer cells grow. Targeted therapies have less effect on healthy cells than chemotherapy drugs.

But Avastin is most often used with chemotherapy. (Whether it is depends on the type of cancer being treated.) So it’s not necessarily a treatment that can help you avoid chemotherapy side effects.

In fact, you may be more likely to have certain side effects from receiving Avastin with chemotherapy than from chemotherapy alone. Ask your doctor if you’ll receive Avastin with chemotherapy, with other cancer treatments, or on its own.

A healthcare professional will give you Avastin by intravenous (IV) infusion once every 2 or 3 weeks. An IV infusion is an injection into a vein that’s given over a period of time. If Avastin works for you, you’ll typically use it on a long-term basis.

For more information about Avastin, including details about its uses, see this in-depth article on the drug.

Like other drugs, Avastin can cause mild or serious side effects. Keep reading to learn more.

Some people may experience mild or serious side effects during their Avastin treatment. Examples of Avastin’s more commonly reported side effects include:

* To learn more about this side effect, see “Side effects explained” below.

Other side effects are also possible with Avastin. Read on to find out more.

Examples of mild side effects that have been reported with Avastin include:

* To learn more about this side effect, see “Side effects explained” below.

In most cases, these side effects should be temporary. And some may be easily managed, too. But if you have any symptoms that are ongoing or that bother you, talk with your doctor or pharmacist. And do not stop using Avastin unless your doctor recommends it.

Avastin may cause mild side effects other than the ones listed above. See the Avastin patient counseling information for details.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Avastin, visit MedWatch.

Serious side effects that have been reported with Avastin include:

* To learn more about this side effect, see “Side effects explained” below.
† An allergic reaction is possible after using Avastin. But it’s not clear whether this side effect occurred in studies.
‡ In this article, we use the term “female” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.

If you develop serious side effects while using Avastin, call your doctor right away. If the side effects seem life threatening or if you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Get answers to some frequently asked questions about Avastin’s side effects.

How long do Avastin side effects last?

Most mild side effects of Avastin tend to improve in a few days or a couple of weeks. If you have side effects that last longer than this or are troublesome, talk with your doctor.

Some serious side effects of Avastin, such as infusion-related reactions, can get better quickly with treatment.

But others may last a long time, even after stopping Avastin and having treatment for the side effect.

In some cases, certain side effects, such as heart failure, kidney problems, or early menopause, may be long term.

Exactly how long side effects may last will depend on how they respond to treatments you may have for them.

If you have questions or concerns about how long Avastin side effects may last, talk with your doctor.

How long does Avastin stay in your system? Does this affect how long the drug’s side effects last?

Not necessarily. Avastin can stay in your system for about 4 months after you stop using it. But its levels decrease steadily over that time. And how long it stays in your system doesn’t always affect how long side effects may last.

Some of Avastin’s side effects may lessen while you continue Avastin treatment. This can happen because your body gets used to the medication.

After you stop treatment, some side effects may last for as long as Avastin stays in your system. Others may ease sooner than this, especially if you receive treatment for them. But in some cases, certain side effects may last even after Avastin is completely gone from your system.

If you have questions or concerns about how long Avastin side effects may last, talk with your doctor.

My doctor recommends Avastin to treat my wet AMD. What side effects are related to eye injections of Avastin?

Avastin is sometimes used off-label to treat wet age-related macular degeneration (wet AMD). Off-label use refers to using a medication for a purpose that hasn’t been approved by the Food and Drug Administration (FDA). Although not approved for wet AMD, Avastin can be effective for helping to prevent loss of vision due to this condition.

To treat wet AMD, a healthcare professional injects Avastin into your eye. They’ll numb your eye first. According to the American Academy of Opthalmology, eye injections of Avastin may cause the following mild side effects:

Serious side effects of these eye injections may include:

  • eye infection
  • detached retina (the retina, a layer of tissue in the eye, has separated from the back of the eye)
  • cataracts (a cloudy area that forms in the eye lens)

To find out more about the possible side effects of Avastin when used for wet AMD, talk with your doctor.

I’m receiving Avastin for brain cancer. Does my condition raise my risk for certain side effects of the drug?

It’s not likely to. In studies of Avastin for treating brain cancer, reported side effects were similar to those that occurred when Avastin was used to treat other types of cancer.

If you’re concerned about your risk of certain side effects with Avastin, talk with your doctor.

Can Avastin cause injection site reactions?

No, Avastin doesn’t typically cause injection site reactions. These are reactions that develop in the area where a medication is injected. They can happen with injections given under the skin or into a muscle.

Avastin is given by IV infusion, which is an injection into a vein that’s given over a period of time. Although it doesn’t cause injection site reactions, Avastin may cause infusion-related reactions. These reactions can result in widespread symptoms throughout the body. They may even be severe enough to require immediate treatment.

To read more about infusion-related reactions with Avastin, see “Side effects explained” below.

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

Infusion-related reaction

You’ll receive Avastin by IV infusion, which is an injection into a vein that’s given over a period of time. Some people may have an infusion-related reaction to Avastin, but this isn’t common.

Infusion-related reactions can cause symptoms throughout your body. These may include:

  • sweating
  • shivering
  • chest pain
  • headache
  • wheezing
  • high blood pressure
  • hypertensive crisis (severe high blood pressure)

Infusion-related reactions are usually mild, but on rare occasions they can be severe and require immediate treatment.

What might help

A healthcare professional will monitor you for symptoms of an infusion-related reaction while you’re having an Avastin infusion. Be sure to tell them right away if you have any symptoms of an infusion-related reaction.

If your symptoms are mild, your healthcare professional may slow down the infusion. This can help your body tolerate it better.

But if your symptoms are more severe, they may stop the infusion until your symptoms lessen. Severe symptoms may need to be treated with medications, such as epinephrine, corticosteroids, intravenous antihistamines, bronchodilators (drugs that open your airways), and oxygen.

Joint pain

Some people may have joint pain during treatment with Avastin. In some studies, joint pain was commonly reported in people who took Avastin with chemotherapy.

Joint swelling and stiffness may also occur alongside joint pain.

What might help

If you have joint pain while using Avastin, talk with your doctor or pharmacist about the best way to manage this. They may recommend some of the following remedies:

  • performing gentle exercise, such as swimming
  • applying hot or cold packs to affected joints
  • using relaxation techniques, such as breathing exercises or meditation

If you have troublesome joint pain, your doctor or pharmacist may also recommend using over-the-counter pain relievers. Examples include acetaminophen (Tylenol) and anti-inflammatory gels, such as diclofenac (Voltaren).

However, you should only take nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) if your doctor says it’s safe for you to do so. This type of painkiller may increase the risk of serious side effects with Avastin, such as bleeding (see “Serious bleeding” below).

Rash

Some people may have a rash during Avastin treatment. In one study, a mild rash was commonly reported in people receiving Avastin. In another study, a more serious type of rash called exfoliative dermatitis was commonly reported in people receiving the drug.

Exfoliative dermatitis is a serious condition that can affect large areas of the body. Symptoms can include:

  • redness, darkening, or discoloration of the skin
  • dry skin
  • itchy skin
  • skin that looks or feels rough and scaly
  • peeling of the skin

What might help

If you have symptoms of exfoliative dermatitis, see your doctor right away. You may need to have this condition treated in a hospital.

If you develop a less severe rash while using Avastin, talk with your doctor or pharmacist about the best ways to manage it.

For example, it may help to keep the area moisturized. Ask your pharmacist to recommend a suitable product. Your doctor or pharmacist may also suggest using certain medications, such as a mild steroid cream.

Be sure to protect your skin from the sun if you have a rash. Wear soft, loose-fitting clothing and a hat. You should also protect your skin from heat and cold, and avoid using scented products on your skin.

Keep in mind that a rash may also be a symptom of an allergic reaction to Avastin. See “Allergic reaction” below to read more about this.

Serious bleeding

People receiving Avastin commonly experience bleeding, especially if they’re also having chemotherapy. This bleeding is usually minor, such as nosebleeds or bleeding gums, but it can also be more serious. For example, serious bleeding can happen in your stomach, intestines, lungs, or brain.

Symptoms of serious bleeding can include:

Before starting Avastin, tell your doctor if you’ve recently coughed up blood. In this case, Avastin may not be safe for you, and your doctor will likely recommend a different cancer treatment.

What might help

To help avoid minor bleeding, be gentle when blowing your nose and brushing your teeth. You should also take extra care to protect yourself from cuts and scrapes.

To stop a nosebleed, tip your head forward and pinch the soft part of your nose just above your nostrils or a few minutes. For bleeding in your mouth, try rinsing your mouth with icy water. If the bleeding won’t stop, call your doctor right away.

If you have symptoms of severe bleeding, call your doctor right away. But if your symptoms feel life threatening, call 911 or have someone take you to the nearest emergency room. If you have severe bleeding, your doctor will likely have you stop treatment with Avastin.

Blood clots

Although uncommon in studies of the drug, Avastin can sometimes cause blood clots to develop inside your blood vessels. These blood clots can cause serious problems, such as:

  • heart attack (when a clot blocks blood flow to the heart muscle)
  • stroke (when a clot blocks blood flow to the brain)
  • ministroke (when a clot temporarily blocks blood flow to the brain)
  • angina (chest pain caused by blocked blood flow to the heart muscle)
  • pulmonary embolism (a blood clot in the lungs)
  • deep vein thrombosis (a blood clot in a vein deep in the body, such as in the leg)

Symptoms of a blood clot may include:

  • chest pain
  • pain in the shoulder, arm, or back
  • shortness of breath
  • fast breathing or heartbeat
  • dizziness
  • sudden numbness or weakness in one side of the body
  • confusion
  • trouble speaking
  • pain, swelling, or warmth in the leg

What might help

If you have symptoms of a blood clot during Avastin treatment, call your doctor right away. But if your symptoms feel life threatening, call 911 or have someone take you to the nearest emergency room.

If you have a blood clot, your doctor will prescribe medication to treat this. They’ll likely have you stop treatment with Avastin.

Allergic reaction

Like most drugs, Avastin can cause an allergic reaction in some people. But it’s not clear whether this side effect occurred in studies.

Symptoms can be mild or serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest an over-the-counter antihistamine you take by mouth, such as Benadryl (diphenhydramine), or a product you apply to your skin, such as hydrocortisone cream, to manage your symptoms.

If your doctor confirms you had a mild allergic reaction to Avastin, they’ll decide if you should continue using it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you had a serious allergic reaction to Avastin, they may have you switch to a different treatment.

Keeping track of side effects

During your Avastin treatment, consider keeping notes on any side effects you’re having. Then, you can share this information with your doctor. This is especially helpful to do when you first start taking new drugs or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of drug you were receiving when you had the side effect
  • how soon after starting that dose you had the side effect
  • what your symptoms were from the side effect
  • how it affected your daily activities
  • what other medications you were also taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help your doctor learn more about how Avastin affects you. And your doctor can use this information to adjust your treatment plan if needed.

Avastin may not be right for you if you have certain medical conditions or other factors that affect your health. Before you start Avastin treatment, talk with your doctor about your health history. The list below includes factors to consider.

Surgery. Avastin can cause problems with wound healing. If you’ve recently had major surgery, you should not start Avastin treatment until any wounds you have are fully healed.

If you have an upcoming surgery planned, your doctor may want you to stop receiving Avastin for 28 days beforehand. If you need emergency surgery during Avastin treatment, you may need to stop treatment if you have problems with wound healing afterward. Your doctor will tell you when it’s safe to receive Avastin after surgery.

Allergic reaction. If you’ve had an allergic reaction to Avastin or any of its ingredients, you should not receive Avastin. Ask your doctor what other medications are better options for you.

High blood pressure. Avastin can increase your blood pressure. If you already have high blood pressure, Avastin could make this worse.

Your doctor will check your blood pressure frequently while you receive Avastin. If your blood pressure gets too high, you may need medication to lower it. Or you may need dosage changes to blood pressure medication you already take.

If your blood pressure remains unmanageable, you may need to stop receiving Avastin.

Past heart attack or stroke. Avastin can sometimes cause serious blood clots that could lead to a heart attack or stroke. If you’ve had a heart attack or stroke in the past, you may have a higher risk for these side effects. Ask your doctor if Avastin is right for you.

Older age. Avastin can sometimes cause serious blood clots that could lead to a heart attack or stroke. If you’re age 65 years or older, you may have a higher risk for these side effects. Ask your doctor if Avastin is right for you.

Alcohol use and Avastin

Drinking alcohol doesn’t affect the way Avastin works. But it might worsen certain side effects, such as headache. Alcohol might also interact with some of the other drugs that Avastin may be used with.

Ask your doctor if it’s safe to drink alcohol during your cancer treatment and, if so, how much is considered safe.

Pregnancy and breastfeeding during Avastin treatment

If you’re pregnant, receiving Avastin could harm your developing fetus. Talk with your doctor about the risks and benefits of this treatment. They may recommend using a different treatment for your cancer.

If you’re able to become pregnant, you should use effective birth control while you’re receiving Avastin. You should continue to use birth control for 6 months after your last dose.

Also, Avastin could affect your ability to get pregnant after treatment. If you want to plan a pregnancy in the future, talk with your doctor before starting Avastin treatment.

It’s not known if Avastin is safe to use during breastfeeding. You should not breastfeed while having treatment with Avastin and for 6 months after your last dose. If you’re breastfeeding or planning to do so, talk with your doctor about other healthy ways to feed your child.

Like many cancer treatments, Avastin can cause side effects, especially if you receive it with chemotherapy. Most side effects are mild and are usually temporary or easily managed.

But serious side effects are also possible, some of which may last a long time. Your doctor will carefully monitor you for these side effects during your treatment. This way, if such side effects happen, they can be detected and treated early.

If you’d like to know more about Avastin’s side effects, talk with your doctor or pharmacist. They can help you decide if this medication is a good option for you. Here are some examples of questions you might like to ask:

  • Does Avastin cause any long-term side effects?
  • Do I have a higher risk for side effects with Avastin due to my other cancer treatments?
  • Does having diabetes raise my risk for side effects?
  • Is there anything I can do to reduce my risk for side effects with Avastin?

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.