Erenumab belongs to the class of medications called calcitonin gene-related peptide receptor antagonists. Erenumab is used to prevent migraine for adults who experience 4 or more migraine days each month.

This medication works by blocking the activity of a protein called calcitonin gene-related peptide. For people suffering a migraine attack, this protein is increased.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The recommended dose of erenumab is 70 mg injected subcutaneously (under the skin) once a month. Depending on how you respond to this medication, your doctor may prescribe a maximum dose of 140 mg injected once a month. Each prefilled syringe or autoinjector of erenumab is single use only and should be safely discarded after the dose has been injected.

Erenumab is administered by subcutaneous injection in the thigh, buttocks, or abdomen. It is important to rotate the site of injection. Allow the medication to reach room temperature by removing it from the refrigerator at least 30 minutes before injecting it. Do not heat the syringe or autoinjector to warm the medication. Do not shake this medication before using it. The solution for injection should be clear-to-slightly-opalescent and colourless-to-slightly-yellow. If it is cloudy or you can see lumps, flakes, or coloured particles in the solution, do not use it.

If you are using this medication at home, your doctor will ensure that you understand exactly how to use it. Make sure you ask any and all questions necessary to ensure that you use it exactly as prescribed. Please refer to the appropriate package insert for details on how to mix the medicine and for proper injection procedures. It is important to visit your doctor regularly during therapy to ensure that the medication is working safely and effectively.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important to take this medication exactly as prescribed by your doctor.

If you miss a dose, take it as soon as possible. The following dose should be given one month after the missed dose has been used. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication in the refrigerator, protect it from light and moisture, and keep it out of the reach of children. Do not allow this medication to freeze. Once this medication has been removed from the refrigerator, it may be kept at room temperature (up to 25°C) for up to 14 days. Do not put erenumab that has reached room temperature back in the refrigerator.

70 mg/mL
Each 1 mL of clear-to-opalescent and colourless-to-light-yellow, preservative-free, sterile solution, contains 70 mg erenumab. Nonmedicinal ingredients: glacial acetic acid, polysorbate 80, sucrose, water for injection, and sodium hydroxide to pH of 5.2.

The needle cover of the glass prefilled syringe and the autoinjector contain natural rubber latex.

140 mg/mL
Each 1 mL of clear-to-opalescent and colourless-to-light-yellow, preservative-free, sterile solution, contains 140 mg of erenumab. Nonmedicinal ingredients: glacial acetic acid, polysorbate 80, sucrose, water for injection, and sodium hydroxide to pH of 5.2.

The needle cover of the glass prefilled syringe and the autoinjector contain natural rubber latex.

Do not take this medication if you are allergic to erenumab or any ingredients of the medication.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• constipation
• hair loss
• itching
• mouth or lip sores
• muscle spasms
• pain, redness, or swelling at the injection site

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Allergic reactions: In rare cases, some people may develop an allergic reaction to this medication. Signs of an allergic reaction include a severe rash, hives, swollen face or throat, or difficulty breathing. If these occur, contact your doctor immediately.

Constipation: Constipation is a possible side effect of erenumab. People who have a history of constipation or take other medications that cause constipation may be more at risk. If you experience constipation, speak to your doctor or pharmacist for advice on how to manage it. If you experience new or increased abdominal pain or difficulty with bowel movements, contact your doctor.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if erenumab passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

Seniors: The safety and effectiveness of using this medication have not been established for people over the age of 65.

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.