Erenumab (Aimovig) is a newer prescription drug you can inject to prevent migraines. The monthly shots can give you fewer headache days a months but can also come with side effects.
Sometimes, side effects start with the first dose of the medication but disappear over time. Others can last longer. And there are some less common side effects of erenumab that can be serious.
Here’s what to look for, as well as some tips to help prevent and manage side effects.
What Are the Most Common Side Effects of Erenumab (Aimovig)?
The two most common side effects are injection-site reactions and constipation.
Injection-site reactions.These happen when your immune system reacts to the needle going into your skin or to the medicine itself. You’ll feel or see these reactions where the needle went in. They include:
- Swelling
- Itching
- Pain
- Redness
- Warm or sore skin
To treat injectionsite reactions, you can:
- Apply a cold pack to the area to lessen swelling and itching.
- Take over-the-counter pain medications such as acetaminophen or ibuprofen. They can reduce inflammation and pain.
Call your doctor if you have any of these more serious symptoms:
- Fever
- Severe pain or blistering at the injection site
- Nausea, dizziness, or headache
- Severe skin rash, itching, vomiting, or hives
There are few things you can do that may make injection site reactions less likely:
- Learn how to inject. Your health care provider can show you how to inject erenumab the right way. That helps the shots hurt less. You can also watch a how-to-inject video at aimovig.com.
- Let erenumab sit at room temperature for at least 30 minutes before injection. A shot of a cold medication hurts more than one at room temperature.
- Relax. When you feel nervous, you may tense your muscles or move around during the injection. This can make it hurt more.
Constipation. Erenumab may change the balance of bacteria in your gut in a way that can make it harder for you to have a bowel movement. About half of people who took the drug in a study had constipation, especially when they had just begun treatment.
To relieve constipation:
- Drink lots of water, which makes your stools softer and easier to pass.
- Try over-the-counter fiber supplements, stool softeners, stimulants, and lubricants. Your doctor may also recommend a laxative.
To prevent constipation:
- Eat fiber-rich foods like lentils, black beans, berries, apples, carrots, broccoli, and almonds.
- Aim to go to the bathroom at the same time each day. A schedule can help keep you regular, which prevents constipation.
What Are Less Common Side Effects of Erenumab (Aimovig)?
Erenumab can cause mild cramps or muscle spasms. They can last a few seconds or a few minutes. If you have cramps or muscle spasms, it may help to:
- Gently stretch or massage the muscle
- Apply a heat pack to tight muscles and a cold pack to sore muscles
To prevent muscle cramps:
- Drink more fluids. Dehydration can worsen cramps and muscle spasms.
What Are the Serious Side Effects of Erenumab (Aimovig)?
This drug isn’t an option if you’ve recently had a heart attack or a stroke. It’s rare, but people taking erenumab can get hypertension, or high blood pressure. Or their hypertension may worsen. This happens most often in the first 7 days of treatment.
If you have high blood pressure or risk factors for it, talk to your doctor before you take erenumab.
High blood pressure doesn’t usually cause symptoms. That’s why you should measure it regularly or have it taken at your doctor’s office. When symptoms do happen, they can include:
- Chest pain
- Irregular heartbeat (too fast or too slow)
- Nosebleeds
- Vision changes
- Fatigue
- Upset stomach
- Vomiting
- Confusion
Call 911 if you have any of these symptoms while taking the medication.
Problems with high blood pressure with erenumab are more likely if you already have risk factors for hypertension. You’re at higher risk if you:
