Stiff Person Syndrome: What to Do When Adjunct Antispasmodic Agents Fail to Control Focal and Painful Spasms

Clinical Scenario

In patients with Stiff Person Syndrome who are already on GABA-enhancing therapy and have been trialled on adjunct antispasmodic agents — including botulinum toxin, methocarbamol, or dantrolene — but continue to experience inadequately controlled focal and painful muscle spasms, escalation to the next treatment protocol is warranted.

Prior Treatment — What Did Not Achieve the Goal

The preceding step added adjunct antispasmodic agents (botulinum toxin for focal spasms, methocarbamol, or dantrolene) on top of background GABA-enhancing therapy. The defined target — meaningful reduction of focal and painful muscle spasms — was not adequately reached. This failure is the trigger for the current protocol.

Next-Step Treatment Approach

This protocol uses intravenous immunoglobulin (IVIg) as the primary immune-based therapy, administered in structured courses. For severe disease exacerbations, a plasma-based adjunct procedure may also be incorporated.

Full regimen details — including schedule, maintenance criteria, and adjunct guidance — are available in the complete protocol below.

Clinical Goals After This Protocol

Reduced stiffness, especially in the paraspinal muscles
Fewer falls and improved gait, including the ability to walk without assistive devices
Substantial reduction of anxiety-triggered spasms
Return to most daily activity functions

Instant Access to Structured Evidence-Based Regimens

References

DOI: 10.1212/NXI.0000000000200109

Plasmapheresis: As an adjunct short-term therapy for exacerbations of severe spasms.

Plasmapheresis may be a viable option as an adjunct therapy for severe disease exacerbations based on a small case series.

Patients experienced reduced stiffness, especially in the paraspinal muscles with more muscle flexibility; less falls; improvement in their gait becoming able to walk without assisted devices; and with substantial reduction of anxiety-triggered spasms becoming able to perform again most of daily activity functions.

This pivotal study has conclusively shown that after 3 monthly infusions, IVIg was effective in up to 75% of patients with SPS who were symptomatic with inadequate response to antispasmodic and GABA-enhancing drugs.

View source ↗