Key takeaways:
Migraine prevention medications help manage migraines that occur frequently. Several of them are FDA approved for this purpose, while others are recommended for off-label use.
Botox (onabotulinumtoxinA) was the first FDA-approved migraine prevention medication. This in-office treatment involves a series of tiny injections just under the skin on your head and neck.
Many calcitonin gene-related peptide (CGRP) monoclonal antibodies are migraine injections you can receive at home or in a medical setting. Brand names include Aimovig (erenumab), Vyepti (eptinezumab), and more.
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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 with the approval of Aimovig (erenumab). Three more monoclonal antibody injections have since followed.
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 for migraines, a healthcare professional 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.
Aimovig
Aimovig (erenumab) is the first FDA-approved monoclonal antibody designed to block the effects of a protein called calcitonin gene-related peptide (CGRP). It does this by binding to either CGRP directly or its receptor (binding site). That’s why Aimovig — and the other medications on this list — are dubbed “CGRP antagonists” (blockers).
Aimovig is administered subcutaneously (under the skin) once per month. It comes in a prefilled pen or syringe and can be injected at home.
Ajovy
Ajovy (fremanezumab) is another CGRP antagonist for preventing migraine. Like Aimovig, it blocks the effects of CGRP, a protein that can trigger migraines. Ajovy is also administered under the skin either monthly or every 3 months.
Emgality
Emgality (galcanezumab) is also a monoclonal antibody used to prevent migraine. In addition to treating migraine, Emgality is also FDA approved to treat cluster headaches. Emgality is injected subcutaneously once per month.
Vyepti
Vyepti (eptinezumab) is another CGRP blocker that’s administered every 3 months to prevent migraine. But unlike the other CGRP blockers, which can be administered at home, Vypeti is given by intravenous (IV) infusion in a medical setting.
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 team 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. Also, easier-to-take oral prevention medications are usually recommended before trying an injection.
How effective are injections 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 professionals 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 team about your options
A 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 healthcare team.
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.
Side effects of 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 team if you’re going to the bathroom less than usual.
High blood pressure: Aimovig can cause high blood pressure, especially within the first week of treatment. Let your team 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 team 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.
Side effects of 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 team 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 team 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 team 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. Oral medications are FDA approved for migraine prevention, such as:
Beta blockers, like propranolol (Inderal LA)
Anticonvulsants, like topiramate (Topamax)
The AHS also recommends some medications to be used off-label. Two of these are:
Candesartan (Atacand), a blood pressure medication
Amitriptyline, an antidepressant
For menstrual migraines, you may find some short-term prevention with nonsteroidal anti-inflammatory drugs (NSAIDs), like:
Ibuprofen (Advil, Motrin)
Frovatriptan (Frova)
Two CGRP blockers for migraine prevention also come in oral form:
Qulipta (atogepant)
Nurtec ODT (rimegepant)
Can migraines be prevented without medication?
Sometimes. Your healthcare team may recommend lifestyle changes to reduce migraine frequency. For some people, migraines can be prevented by:
Avoiding triggers such as smoking or alcohol
Limiting caffeine consumption
Regular physical activity
Maintaining or working toward your target body weight
Getting enough sleep
Staying well-hydrated
Unfortunately, following these tips may not be enough to prevent migraine. That’s when your healthcare team may discuss medications for migraine.
When should you see a doctor about migraines?
Migraines can cause severe, debilitating head pain. That’s in addition to symptoms like vision changes, nausea, and vomiting. Some people develop weakness or tingling in their arms or legs during a migraine. It can be difficult to tell apart a severe migraine from other more dangerous conditions.
In general, you should seek emergency care for a headache that:
Comes with fever and neck stiffness
Is the worst headache of your life
Starts abruptly and escalates within seconds
Happens after a head injury
Causes loss of consciousness or altered mental status
Is worse with changes in position
Frequently asked questions
Migraine triggers can vary from person to person. But some common triggers include:
Smoking
Alcohol
Chocolate
Stress
Dehydration
Changes in sleep
Odors
For some people, Botox injections don’t hurt at all. Others describe injections as a pinprick, or a poking, pinching, or stinging sensation. Some people say certain injection sites on the body hurt more than others. Pain levels vary from person to person.
Migraine triggers can vary from person to person. But some common triggers include:
Smoking
Alcohol
Chocolate
Stress
Dehydration
Changes in sleep
Odors
For some people, Botox injections don’t hurt at all. Others describe injections as a pinprick, or a poking, pinching, or stinging sensation. Some people say certain injection sites on the body hurt more than others. Pain levels vary from person to person.
The bottom line
Botox and calcitonin gene-related peptide (CGRP) monoclonal antibodies like Aimovig (erenumab) are FDA approved to prevent migraines. You’ll usually try other migraine medications before these injections are recommended. They can take some time to work too. It can take up to 3 to 6 months to get the full benefit of monoclonal antibodies — and up to 6 to 9 months for Botox injections.
Why trust our experts?
References
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