A. Questions to ask before initiating treatment: | |
1) “Does the patient really have dystonia?” | |
- Exclude pseudodystonia and psychogenic dystonia | |
2) “Is there any (etiology-) specific treatment for the patient?” | |
- Identify treatable dystonia (Table 2): neurometabolic disorders (DRD being the most important), heavy metal-related disorders (especially Wilson’s disease) and acquired disorders | |
3) Is there any coexisting phenomenology other than dystonia? | |
- Identify and appropriately treat coexisting phenomenology such as parkinsonism (e.g. in RDP) or myoclonus (e.g. in myoclonus-dystonia syndrome or DYT11 dystonia) | |
4) “What treatment modality or modalities should be initiated?” | |
- Selecting between medications vs. BoNT vs. DBS or combination (Table 3) | |
B. General principles of symptomatic medical treatment in dystonia | |
• Trihexyphenidyl is a first-line agent • Baclofen and clonazepam are typically second-line agent • TBZ or clozapine may be considered as first-line agents in tardive dystonia • Start low, go slow o Initiate at a low dose o Titrate up slowly ▪ Every 3–4 days in children and younger adults ▪ Every 1 week for older adults or patients prone to side effects • Continue uptitration if non-sustained benefits or inadequate symptom control • If side effects occur – may initially try holding the dose constant. If no improvement, or severe/intolerable side effects – lower the dose (modified from Ref [5]) o If side effects disappear and patient still benefits: ▪ Consider combination therapy or try increasing the dose slowly again o If side effects disappear but no benefit: ▪ Consider discontinuation (may need slow tapering especially baclofen and clonazepam) o If side effects persist but patient still benefits: ▪ Consider lowering the dose further o If side effects persist and no benefit ▪ Consider discontinuation (or slow tapering) o If benefits are seen and symptoms are adequately controlled: ▪ Hold constant to see if benefits are sustained. • Of note, sometimes trihexyphenidyl at a constant dose may require 2–4 weeks to reach peak benefit • Trihexyphenidyl may have paradoxical effects at low doses o If this occurs – may try pushing to higher doses slowly |