‘A Paradigm Shift’: CGRP Inhibitors and the Essential Role of the Physical Therapist in Migraine Management

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The introduction of Calcitonin Gene-Related Peptide (CGRP) inhibitors marks a significant leap in the pharmacological management of migraine. For too long, repurposed drugs from other classes, such as anti-hypertensives or anti-epileptics, served as the primary preventive medications. The advent of this targeted class of therapy begins a new era in patient care. As physical therapists specializing in balance and dizziness, we must not only comprehend this medication class but also acknowledge our pivotal and complementary role in treating patients with these conditions.

The CGRP Revolution: What it Means for Migraine

Migraine is not just a severe headache; it is a complex neurological disorder. Research identifies CGRP, a neuropeptide, as a key player in the cascade of events that trigger pain and its associated symptoms. High levels of CGRP lead to vasodilation and activation of nerve pathways, thereby amplifying pain signals.

CGRP inhibitors work by stopping this process. They fall into two main categories:

• CGRP Monoclonal Antibodies (mAbs): These are biological agents that block either the CGRP molecule itself (ligand) or its receptor on the nerve cell. Physicians prescribe these for the ‘prevention’ of chronic or episodic migraine. They use an injection or an intravenous infusion.

  • Examples include Erenumab, Fremanezumab, Galcanezumab, and Eptinezumab.

• CGRP Receptor Antagonists (Gepants): These are small-molecule oral drugs that block the CGRP receptor. Physicians prescribe these for both ‘acute treatment’ (to stop an attack once it begins) and ‘prevention.’

  • Examples include Rimegepant, Ubrogepant, and Atogepant.

This targeted approach delivers significantly improved outcomes for many patients. However, the patient’s migraine journey involves more than simply reducing headache frequency; it consists of addressing the pervasive symptoms that impact their physical function and quality of life—specifically dizziness and balance.

The CGRP/Vestibular Connection: A Critical Link for Physical Therapists

As specialists, we know that vestibular symptoms are profoundly common. Vestibular Migraine (VM) affects 30% to 50% of migraine sufferers, making it a significant cause of vertigo. Emerging research suggests that CGRP directly influences the inner ear and the central nervous system structures responsible for balance.

Studies on the CGRP pathway demonstrate a clear connection:

• Elevated CGRP and Imbalance: Research shows that heightened CGRP levels can directly affect vestibular end organ potentials and increase sensory hypersensitivities, leading to postural instability and motion-induced anxiety, symptoms highly relevant to ‘Vestibular Migraine.’

• The Vestibular-Anxiety Loop: CGRP is not just about pain. Studies find that a combination of elevated CGRP and a vestibular challenge (like rotation) promotes anxiety-like behaviors and dynamic imbalance in animal models. This supports the clinical observation of motion-induced anxiety and agoraphobia in our patients with VM.

When a patient starts CGRP therapy, they are actively altering their neurochemistry to reduce the frequency of attacks. Physical therapists must capitalize on this reduction in central sensitization to effectively treat the residual or comorbid balance and dizziness dysfunction.

The Physical Therapy Imperative: Optimizing Patient Outcomes

CGRP inhibitors are a pharmacological tool; physical therapy is the ‘functional tool’ that integrates the patient back into their life. The new wave of pharmacological agents does not eliminate the need for our expertise; it amplifies it.

We use Vestibular Rehabilitation to address the patient’s long-standing physical deficits, which persisted despite pharmacological improvements:

• Adaptation Exercises: We prescribe gaze stabilization exercises to improve the gain of the Vestibulo-Ocular Reflex (VOR) and the Vestibulo-Collic Reflex (VCR), as well as balance exercises to enhance the Vestibulo-Spinal Reflex (VSR). These targeted exercises encourage the central nervous system to recover function in cases of vestibular hypofunction, which often presents as visual or surface dependency.

• Habituation Training: We design specific movements or activities that reproduce symptoms (like dizziness or visual sensitivity) to reduce the patient’s pathological response over time. This desensitizes the central nervous system to motion and visual-motion stimuli, directly addressing symptoms of Vestibular Migraine.

• Substitution and Sensory Training: When a profound loss of inner ear function exists, we teach the patient to rely on reliable visual and somatosensory (surface) cues. We use active balance training, often on dynamic surfaces, to challenge and improve their ability to use alternative sensory inputs for postural control.

Our role is not secondary; we are essential partners in a multidisciplinary team. When a CGRP inhibitor reduces the chemical burden of migraine, we step in to resolve the long-standing physical dysfunctions. By combining pharmacological innovation with the power of physical therapy, we give our patients the ‘best chance’ at regaining their lives. This collaborative approach, where each team member plays a crucial role, ensures the comprehensive care and recovery of our patients.

About the Author

Brian Werner, PT, MPT, is a physical therapist who has been specializing in vestibular and balance disorders for over a quarter of a century. He is the founder of the FYZICAL Balance Paradigm and one of the co-founders of FYZICAL, LLC, Balance Center Division with Dr. Daniel Deems, MD, PhD, where he serves as the National Director of Vestibular Education & Training. His background as a gymnast and a traditional rock climber instilled in him a deep understanding of balance, coordination, and movement, which he later applied to his career in physical therapy.