Ajovy (fremanezumab) is a prescription medication used to prevent migraine attacks. It is FDA-approved for preventive treatment of migraine in adults and for preventive treatment of episodic migraine in children ages 6 to 17 who weigh at least 99 pounds (45 kg). It does not treat a migraine once one has started; instead, it reduces how often attacks occur in the first place.
How Ajovy Prevents Migraines
Ajovy belongs to a class of medications that target a protein called CGRP (calcitonin gene-related peptide). CGRP plays a key role in triggering migraine attacks. During a migraine, CGRP levels spike, causing blood vessels around the brain to dilate and activating pain pathways. Ajovy works by binding directly to CGRP before it can attach to its receptor, essentially neutralizing the protein and blocking the chain reaction that leads to a migraine.
This makes Ajovy different from older preventive medications like blood pressure drugs or antidepressants that were borrowed from other uses. It was designed specifically for migraine prevention, which is why it tends to cause fewer unrelated side effects than those older options.
Who It’s Designed For
Ajovy is meant for people who experience frequent migraines, whether episodic (fewer than 15 headache days per month) or chronic (15 or more headache days per month, with at least 8 of those being migraine). If you’re having four or more migraine days per month, your doctor may consider preventive treatment. Ajovy is one of several CGRP-targeting options now available for this purpose.
In pediatric patients with episodic migraine, clinical trials showed that Ajovy reduced monthly migraine days by an average of 2.5 days compared to 1.4 days with placebo, a statistically significant difference.
Dosing Options: Monthly or Quarterly
One of Ajovy’s practical advantages is dosing flexibility. You can choose between two schedules:
- Monthly: One injection of 225 mg
- Quarterly: Three injections of 225 mg each (675 mg total), given back to back every three months
Both options are self-administered as subcutaneous injections, meaning you inject just under the skin, typically in the thigh, abdomen, or upper arm. The medication comes in prefilled syringes or autoinjectors. If remembering a monthly shot feels like a hassle, the quarterly option means you only deal with it four times a year.
Common Side Effects
Ajovy has a relatively mild side effect profile. The most common adverse reaction in clinical trials was irritation at the injection site, including pain, redness, and hardness. This occurred in about 43% to 45% of people taking Ajovy, compared to 38% on placebo, so the difference attributable to the drug itself is modest. Only about 1% of trial participants stopped treatment because of injection site reactions.
Serious allergic reactions are rare but possible. Signs include hives, difficulty breathing, or swelling of the face, lips, tongue, or throat. Notably, an allergic reaction can show up as late as one month after an injection, so it’s worth being aware of these symptoms even weeks later. Ajovy should not be used by anyone with a known allergy to the active ingredient.
How to Store Ajovy at Home
Ajovy needs to be kept in the refrigerator between 36°F and 46°F (2°C to 8°C), in its original carton to protect it from light. If you need to take it out, for travel, for instance, it can stay at room temperature (up to 86°F or 30°C) for a maximum of 7 days. After those 7 days at room temperature, any unused medication must be discarded. Once it’s been out of the fridge, you cannot put it back in. Do not freeze it, expose it to extreme heat or direct sunlight, or shake it.
Before injecting, let the prefilled syringe or autoinjector sit at room temperature for about 30 minutes. Injecting cold medication tends to be more uncomfortable.
What to Expect After Starting
Preventive migraine medications generally need some time to show their full effect. Many people notice a reduction in migraine frequency within the first month, but it can take two to three months to see the full benefit. If Ajovy hasn’t made a meaningful difference after three months, it’s reasonable to reassess with your prescriber whether to continue or try a different approach.
Ajovy does not eliminate migraines entirely for most people. The goal is a significant reduction in how many days per month you experience attacks. You can still use your usual acute migraine treatments (like triptans or over-the-counter pain relievers) for breakthrough migraines while on Ajovy.