How quickly does Aimovig start reducing migraines?
Aimovig (erenumab) begins working within one week for some patients, with noticeable migraine reduction often seen after the first monthly dose. Full effects typically build over 1-3 months of consistent use, as it targets CGRP receptors to prevent migraines rather than treating acute attacks.[1][2]
What do clinical trial results show for onset?
In the pivotal Phase 3 trials (e.g., STRIVE study), patients on 70 mg monthly Aimovig had 50% fewer monthly migraine days by month 3 compared to placebo. About 40-50% of participants achieved at least 50% reduction in migraine frequency after 3 months, with early responders showing benefits by week 1. No immediate relief occurs during a migraine—it's preventive only.[1][3]
Why might it take weeks or months to feel the full effect?
Aimovig blocks CGRP, a protein involved in migraine pathways, but steady blood levels and receptor occupancy take time. Individual factors like migraine severity, prior treatments, and genetics influence speed—some see relief in days, others need 2-3 doses.[2][4]
When should you expect peak effectiveness?
Most patients reach maximum benefit by month 3. If no improvement after 3 months, doctors often reassess dosing (70 mg or 140 mg monthly) or switch therapies.[1][5]
What if it doesn't work right away—patient experiences?
Real-world reports on forums and studies note variability: 30-40% respond within the first month, but 20% may need longer or not respond. Switching to injectables like Emgality or oral gepants is common if ineffective.[4][6]
How does Aimovig's onset compare to other CGRP preventives?
| Drug | Onset Timeline | Dosing |
|------|----------------|--------|
| Aimovig | 1 week initial, full by 1-3 months | Monthly subQ |
| Emgality | 1 month for many | Monthly/quarterly subQ |
| Ajovy | 1 week possible, full by 1 month | Monthly/quarterly subQ |
| Nurtec ODT (acute + preventive) | Hours for acute attacks | As needed oral |
Aimovig matches peers for preventives but lacks acute relief options.[2][7]
[1]: Aimovig Prescribing Information (Amgen)
[2]: FDA Approval Summary for Aimovig
[3]: NEJM Study on Erenumab (STRIVE trial, 2017)
[4]: American Headache Society Guidelines (2021)
[5]: Neurology Journal Review on CGRP Monoclonals (2020)
[6]: Patient-reported outcomes from Migraine Impact Report (Amgen, 2022)
[7]: Comparative efficacy meta-analysis, Headache Journal (2022)