Calcitonin Gene-Related Peptide in Migraine
Trigger
Trigeminal Activation
Sensory neurons innervating meningeal vessels activated
→
Release
CGRP Released
Elevated in jugular blood during migraine attack
→
Effects
Meningeal Effects
Vasodilation + neurogenic inflammation + pain sensitization
→
Result
Migraine Pain
Central sensitization — allodynia in established migraine
CGRP Drug Classes vs Triptans — Key Comparisons
| Feature |
Ubrogepant |
Rimegepant |
Atogepant |
Erenumab |
Fremanezumab / Galcanezumab / Eptinezumab |
| Class |
Gepant |
Gepant |
Gepant |
Monoclonal antibody |
Monoclonal antibody |
| Target |
CGRP receptor |
CGRP receptor (RAMP1) |
CGRP peptide |
| Acute use |
Yes |
Yes |
No |
No |
No |
| Preventive use |
No |
Yes |
Yes |
Yes |
Yes |
| Route |
Oral |
Oral (ODT) |
Oral |
SC monthly |
SC monthly/quarterly; IV quarterly (eptinezumab) |
| Vasoconstriction |
No |
No |
No |
No |
No |
| Safe in CV disease |
Yes |
Yes |
Yes |
Caution* |
Caution* |
| Key adverse effect |
Nausea |
Nausea |
Constipation, nausea |
Constipation, injection site reaction |
Injection site reaction |
* Caution: patients with recent MI or stroke excluded from pivotal trials — safety in active CV disease not fully characterized.