What Injections Are Available for Migraine Prevention? Monoclonal Antibody Treatments and More

Many people are bothered by a headache every now and then. But migraines are more than just bad headaches. Migraines can last for hours — even days — and involve symptoms beyond severe head pain. Nausea, vomiting, and sensitivity to light or sound can put an immediate halt to your plans for the day.

Thankfully, the list of medications available to treat or prevent migraines keeps growing. Many of them are injectable products. 

In this guide on migraine prevention injections, we’ll highlight Botox and newer monoclonal antibody medications — how they work, when they’re used, and side effects you can expect.

What types of migraine prevention injections are available?

In 2010, Botox (onabotulinumtoxinA) became the first FDA-approved migraine prevention medication. Then, in 2018, another option became available. This is when Aimovig (erenumab) was approved. Three more monoclonal antibody injections have since followed in Aimovig’s footsteps.

Botox injections for migraines

You’ve probably heard of Botox Cosmetic. It’s a popular remedy for reducing the appearance of facial lines. Botox for migraines contains the same active ingredient, but it's approved for medical uses.

If you’re prescribed Botox, your healthcare provider will inject a series of small injections, each containing 5 units of Botox. Typically, 31 injections are given across 7 areas of your head and neck. Treatment is repeated every 3 months for ongoing migraine prevention.

Monoclonal antibody injections

Monoclonal antibody injections for migraines are human-made antibodies (proteins) designed to block the effects of a protein called calcitonin gene-related peptide (CGRP). They do this by binding to CGRP directly, or its receptor (binding site). They’re dubbed “CGRP antagonists” (blockers).

With the exception of Vyepti, you can administer injectable CGRP blockers at home under your skin. They come in prefilled autoinjectors or syringes. Vyepti is an intravenous (IV) infusion into a vein that’s given in a medical setting.

Listed below are currently available products and their recommended dosages:

• Aimovig: 70 mg to 140 mg once monthly

• Ajovy (fremanezumab): 225 mg once monthly (or 675 mg every 3 months)

• Emgality (galcanezumab): 240 mg (first dose) then 120 mg once monthly

• Vyepti (eptinezumab): 100 mg to 300 mg IV every 3 months

Note: Emgality is also FDA approved to treat cluster headaches. You’ll likely receive 300 mg for your first dose and then 300 mg once monthly until headaches subside.

How do migraine injection medications help prevent migraines?

If you have migraines, blocking CGRP is a good thing. Here’s why: CGRP proteins contribute to migraines by widening blood vessels in the brain. They can also cause inflammation and increase sensitivity. Studies show that levels of CGRP are higher for people who experience chronic migraines (15 or more headache days a month).

Botox, on the other hand, is a purified form of a neurotoxin. It blocks CGRP’s release and interferes with a neurotransmitter (chemical) called acetylcholine. This helps prevent migraines by relaxing muscles in the areas where Botox is injected.

Who is a good candidate for migraine injections for prevention?

CGRP injections are approved for use in adults. Botox, however, is approved for a more specific group of people. It can prevent migraines among adults who have chronic migraines, with headaches lasting at least 4 hours.

Otherwise, deciding if a migraine injection medication is right for you is a personal decision. For newer monoclonal antibody treatments, the American Headache Society (AHS) recommends talking with your healthcare provider to find out if they’re a good option for you.

In general, migraine injections are prescribed for people with more frequent or intense migraines — especially when acute migraine medications are often needed. What’s more, easier-to-take oral prevention medications are usually recommended before trying an injection.

How effective are CGRP monoclonal antibodies for preventing migraines?

There are a few ways to assess migraine medication effectiveness. But if a medication helps you have 50% fewer migraines than normal, experts often consider it to be effective. Clinical trials suggest that a greater percentage of people receiving monoclonal antibodies achieve at least a 50% reduction in migraine days compared to those receiving placebo (dummy injection).

After first starting a CGRP blocker, you might notice fewer migraine days within the first month. But healthcare providers try to give these medications about 3 to 6 months before deciding if they’re beneficial. If you’re not seeing much benefit after 3 to 6 months, talk to your provider about your options.

How effective is Botox for preventing migraines?

A recently published systematic review found that Botox was effective in reducing the frequency of migraines. However, it might take some time to see Botox’s full preventative benefits. Full benefits are usually seen after the second or third treatment. If you’re not seeing much benefit after 6 to 9 months, talk to your provider.

What side effects are associated with migraine prevention injections?

Migraine prevention injections are generally well tolerated, but there are some potentially unwanted side effects to consider.

CGRP monoclonal antibody injections

All CGRP blockers could cause an allergic reaction. But some side effects are only linked to specific products, as detailed below:

• Cold-like symptoms. If you’re receiving Vyepti infusions, temporary cold symptoms, like a stuffy nose or scratchy throat, are possible.

• Constipation. Based on initial clinical trials, only Aimovig was associated with constipation. But real-world data suggest constipation might be possible with other types, too. Tell your healthcare provider if you’re pooping less than usual.

• High blood pressure. Aimovig can cause high blood pressure, especially within the first week of treatment. Let your provider know if you notice an increase in blood pressure. 

• Muscle spasms or cramps. These are linked to higher Aimovig doses.

• Injection site reaction: Pain, redness, and swelling can occur around the area where the shot was given. Close to half of people using Ajovy experienced this, but it’s possible with every migraine injection.

• Infusion-related reaction. This can occur during a Vyepti infusion. Signs include flushing, itchiness, or trouble breathing.

• Allergic reaction. Tell your provider right away if you develop a rash, hives, and swelling. A widespread rash, trouble breathing, and nausea after an injection are signs of a life-threatening allergic reaction. Call 911 or seek immediate medical attention.

Botox injections

Common Botox side effects include headache and neck pain. You can use your usual pain relief medication to feel better. But for severe or persistent pain, let your healthcare provider know.

More serious Botox side effects happen if the medication spreads to other parts of your body. Rarely, this can cause breathing or swallowing problems. This is a key reason why Botox should only be administered by a trained healthcare professional.

Allergic reactions are also possible. Your healthcare provider will monitor you for a reaction. Reach out to them if you notice more redness and swelling after leaving their office. But for severe symptoms, call 911 or seek immediate medical attention.

Can injectable triptans prevent migraines?

No. Triptans, like sumatriptan (Imitrex) and zolmitriptan (Zomig), only work when you take them after migraine pain has started. They’re used to treat active migraines.

If you’ve started migraine prevention injections, your healthcare provider may also recommend having medication on hand for breakthrough migraines. These can include oral, intranasal, or injectable triptans.

Do any oral medications prevent migraines?

Yes. Beta blockers, like propranolol (Inderal LA), and anticonvulsants, like topiramate (Topamax), are FDA approved for migraine prevention. The AHS also recommends some medications to be used off-label. A couple of these include candesartan (Atacand), a blood pressure medication, and amitriptyline, an antidepressant.

For menstrual migraines, NSAIDs, like ibuprofen (Advil, Motrin), and frovatriptan (Frova) might provide some short-term prevention.

Two CGRP blockers also come in oral form: Qulipta (atogepant) and Nurtec ODT (rimegepant). But the AHS generally recommends trying other oral medications for migraine prevention first.

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Written by:

Daphne Berryhill, RPh

Daphne Berryhill, RPh, has two decades of experience as a clinical pharmacist. She spent most of her career in the Chicago area practicing in-home infusion.

Edited by:

Joshua Murdock, PharmD, BCBBS

Joshua Murdock, PharmD, BCBBS, is a licensed pharmacist in Arizona, Colorado, and Rhode Island. He has worked in the pharmacy industry for more than 10 years and currently serves as a pharmacy editor for GoodRx.

Reviewed 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.

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