From the FDA Drug Label
AJOVY may cause serious side effects, including: Allergic reactions. Allergic reactions, including itching, rash, and hives, can happen within hours and up to 1 month after receiving AJOVY Call your healthcare provider or get emergency medical help right away if you have any of the following symptoms of an allergic reaction: swelling of your face, mouth, tongue, or throat trouble breathing The most common side effects of AJOVY include: injection site reactions
The potential adverse effects of Ajovy (fremanezumab) include:
- Allergic reactions: itching, rash, hives, swelling of the face, mouth, tongue, or throat, and trouble breathing
- Injection site reactions These side effects can occur within hours and up to 1 month after receiving Ajovy 1
From the Research
Ajovy (fremanezumab) can cause several potential adverse effects, with the most common being injection site reactions, which are typically mild to moderate in severity and tend to diminish over time. The most common side effects of Ajovy include injection site reactions such as pain, redness, or hardening of the skin at the injection location, which typically resolve within a few days 2. Some patients experience hypersensitivity reactions, including rash, itching, and in rare cases, serious allergic reactions. Constipation is another relatively common side effect. Less frequently, patients may experience vertigo or dizziness. There have been reports of hypertension in some individuals taking Ajovy. Importantly, patients with certain cardiovascular conditions should use this medication with caution, as there is theoretical concern about worsening cardiovascular disease, though this risk appears low in practice 3. Some patients report muscle spasms or cramps. The medication may also cause temporary hair loss in rare cases.
Key Adverse Effects
- Injection site reactions (pain, redness, hardening of the skin)
- Hypersensitivity reactions (rash, itching, serious allergic reactions)
- Constipation
- Vertigo or dizziness
- Hypertension
- Muscle spasms or cramps
- Temporary hair loss Most side effects are mild to moderate in severity and tend to diminish over time as the body adjusts to the medication. If severe reactions occur, patients should seek immediate medical attention and discuss with their healthcare provider whether to continue treatment. A recent case report highlighted a delayed injection site reaction to fremanezumab, which presented as warm, red annular plaques 8 days following a second injection, and was relieved with a 1-month course of prednisone 4.