• Blocking intestinal calcitonin gene-related peptide (CGRP) with a CGRP antagonist such as Aimovig (erenumab-aooe), a medicine used for migraine prevention, may lead to constipation, which can be severe in some patients.
• The gastrointestinal (digestive) tract contains CGRP proteins. Some studies suggest that CGRP may play an important role in maintaining the movement of the bowels.
• Most people who develop constipation with Aimovig do so after the first injection, but it can occur later, too. If you develop constipation while taking Aimovig, contact your doctor for management.

Is constipation common with Aimovig?

Constipation is reported as a common side effect with the use of Aimovig.

• Constipation was one of the most common adverse reactions reported in clinical studies, occurring in up to 3% of patients (3 out of 100 patients).
• Patients receiving the higher monthly dose of Aimovig (140 mg) had a greater incidence of constipation (3%) compared to those receiving the 70 mg dose (1%).

In some people, the constipation with Aimovig can be severe and lead to serious complications. Hospitalization or surgery may be needed in some cases. Contact your doctor immediately if you have severe constipation so it can be managed.

In most people who developed constipation, the constipation was reported after their first dose of Aimovig. However, constipation has also occurred later in treatment. In those who developed serious constipation, treatment with Aimovig was stopped. Your doctor should monitor you for constipation and manage it as needed. Do not stop taking your medicine without first talking to your doctor.

Using other medications that can cause constipation may increase your risk for more severe constipation and constipation-related complications. Discuss this with your doctor.

Which CGRP inhibitors cause constipation?

Not all CGRP inhibitors have been associated with constipation. There are three other FDA-approved CGRP inhibitors, including:

• Ajovy (fremanezumab-vfrm)
• Emgality (galcanezumab-gnlm)
• Vyepti (eptinezumab-jjmr)

According to the manufacturer’s data, none of these agents have been linked with constipation. Ajovy, Emgality and Vyepti bind to the CGRP ligand and block CGRP from binding to the receptor, while Aimovig binds to and blocks the actual CGRP receptor site.

However, the constipation due to Aimovig was reported post-marketing (after the drug was approved). It is not known if post-marketing reports will eventually link the other CGRP agents with constipation.

What other side effects occur with Aimovig treatment?

Beside constipation, other common side effects with Aimovig include injection site reactions (pain, redness, or swelling).

Aimovig can also cause serious allergies, high blood pressure or worsening of high blood pressure, and cramps and muscle spasms.

Call your health care provider or get emergency medical help right away if you experience:

• swelling of the face, mouth, tongue, or throat
• have trouble breathing.

These are all signs of a possible allergic reaction.

See also:
Aimovig side effects (in more detail)

These are not all the possible side effects of Aimovig. For more information, ask your doctor, nurse or pharmacist.

Bottom Line

• Some research suggests that CGRP may play an important role in maintaining the movement of the bowels.
• Blocking intestinal CGRP with a CGRP antagonist such as Aimovig (erenumab-aooe), a medicine used for migraine prevention, may lead to constipation, which can be severe in some patients.
• Most people who develop constipation do so after the first injection, but it can occur later, too. If you develop constipation while taking Aimovig, contact your doctor.

This is not all the information you need to know about Aimovig (erenumab-aooe) for safe and effective use. Review the full product information, and discuss this information with your doctor or other health care provider.