Is weight gain a side effect of Aimovig?

Medically reviewed by Dr. Jamie Winn
Aug 21, 2023

While it is thought that genetics play a significant role in migraines, there are other factors that can contribute to you developing migraines. Your risk of chronic migraines increases as you gain weight. Those who are at a healthy weight have around a 3% chance of developing chronic headaches while those suffering from obesity have 3 to 5 times that chance.

If you are overweight and have migraines, the extra weight puts you at a higher risk for more frequent and severe headaches. And weight gain is a side effect of some migraine prevention meds, including Inderal (propranolol) and Depakote (divalproex sodium). Aimovig is another medication used for the preventative treatment of migraines in adults. Clinical studies of Aimovig did not report either weight gain or weight loss as a side effect. However, any weight changes seen while on Aimovig may be attributed to other causes or medical conditions.

Keep reading for the most common side effects of Aimovig, how it works, and other important information.

What is Aimovig?

Aimovig (erenumab-aooe) is a once-monthly subcutaneous (under the skin) injection that is manufactured by Amgen and Novartis. It is FDA-approved to prevent episodic migraine and chronic migraine headaches. It is typically used if other migraine medications such as triptans don’t work or you cannot take them because of side effects or drug interactions.

How does Aimovig work?

Aimovig is a prescription medication that contains the active ingredient, erenumab-aooe. It is a monoclonal antibody that belongs to a class of drugs called calcitonin gene-related peptide (CGRP) receptor antagonists. CGRP is a protein that is thought to cause inflammation in your brain which can lead to migraine attacks. Aimovig works by blocking CGRP proteins in your brain and nervous system. This reduces inflammation and helps stop the vasodilation (widening of your blood vessels) in your brain associated with migraine symptoms.

How often can I take Aimovig?

Aimovig comes as 70 mg or 140 mg prefilled syringes or SureClick autoinjector pens. The recommended dose of Aimovig is 70 mg injected once a month under the skin of your stomach, thigh, or upper arm. If this dose is not effective, you can increase it to 140 mg once a month. You should not take this medication more often than once a month.

What are the side effects of Aimovig?

The most common side effects reported in clinical trials include:

Injection site reactions (redness, swelling, pain)
Mild constipation (fewer than 3 bowel movements per week)

Other side effects of Aimovig may include:

Muscle spasms
Hair loss
Mouth ulcers
Rash

Rarely, Aimovig can cause serious side effects, including:

Serious, life-threatening allergic reaction (hives, itching, swelling of the face, mouth, tongue, or throat, and trouble breathing)
Severe constipation with serious complications that may require hospitalization or surgery
High blood pressure (hypertension)

These are not all of the possible side effects of Aimovig. You should always seek medical advice from your healthcare professional for any questions or concerns about your medical condition or treatment. Read all prescribing information, medication guides, or drug information sheets that come with this medication. You can also report adverse effects to the FDA at www.fda.gov/medwatch or 1-800-FDA-1088.

Does Aimovig injection cause weight gain?

In clinical studies, weight gain was not reported as a side effect of Aimovig. If you notice unusual changes in your weight while taking this medication, contact your healthcare provider immediately as it could be a sign of another medical condition.

What should you tell your healthcare provider before taking Aimovig?

Before starting Aimovig, inform your healthcare provider about any medical conditions you have, including allergies to rubber or latex or if you are pregnant, plan on becoming pregnant, or are breastfeeding.

It is not known if Aimovig will harm your unborn baby. There is a registry for pregnant women taking Aimovig that is used to collect information about you and your baby’s health. You may enroll by visiting https://www.genesispregnancyregistry.com/ or calling 1-833-244-4083.

It is not known if Aimovig will pass into your breast milk. Talk to your healthcare provider about the best way to feed your baby while using this medication.

Make sure you also tell your healthcare provider about any other medications you take as they may cause drug interactions. This includes prescription drugs, over-the-counter medicines, vitamins, or herbal supplements.

How long does it take Aimovig to work?

For some people, it may only take 1 month for Aimovig to start reducing the number of migraine days they experience. However, for most people, it will take 2 to 3 months before they see the full effect.

For those with episodic migraine, taking Aimovig reduced their number of migraine days by an average of 3 to 4 fewer days per month. For those with chronic migraine, taking Aimovig lowered their number of migraine days by an average of around 7 fewer days per month.

Which migraine medication causes weight gain?

Weight gain has not been reported as a side effect of Aimovig in clinical trials conducted by its manufacturer. However, there are other medications used for the prevention of migraine that are known to cause weight gain. Tricyclic antidepressants (TCAs) like Elavil (amitriptyline) and Sinequan (doxepin) that are used to prevent migraines are associated with weight gain. Some beta-blockers that are also used for migraines such as Inderal LA (propranolol ER) and Lopressor (metoprolol) are linked to weight gain. Seizure medications used for migraine prevention, including Neurontin (gabapentin) and Depakote ER (divalproex sodium ER), may also cause you to gain weight.

What is the cost of Aimovig?

The cost of Aimovig will depend on if it is covered by your insurance. If your insurance does not cover Aimovig, it can be very expensive. The average retail cost of Aimovig is around $850 for one autoinjector pen, which is a one-month supply.