OBJECTIVE: To evaluate the clinical utilization of Dysport and BOTOX for cervical dystonia and blepharospasm. Botulinum toxin (BTX) is safe and effective therapy for cervical dystonia and blepharospasm. Two serotype-A toxins, Dysport and BOTOX, are widely prescribed, yet actual clinical utilization is poorly defined or understood. Previous efforts to compare products have been limited by sample size or study designs that mandate drug usage according to protocol. Utilization in actual clinical practice is more appropriate to determine the true effective dose and dose ratios. METHODS: Two sites where BTX is prescribed for cervical dystonia and blepharospasm were identified in the UK (Bristol and Hull) as part of a retrospective observational study. Each site culled BTX data from medical records of patients who received Dysport before switching to BOTOX. RESULTS: Assessment of 29 patients (14 cervical dystonia, 15 blepharospasm) provided a total of 456 injections for computation of mean dose, which was 839.6 ± 308.5 units (Dysport) versus 162.8 ± 64.9 units (BOTOX) for cervical dystonia; and 109.9 ± 33.9 units (Dysport) versus 23.5 ± 8.0 units (BOTOX) for blepharospasm. The ratios of mean dose ranged from 2:1 (Dysport to BOTOX units) to 9:1 (Dysport to BOTOX units), with over 79% of patients utilizing a ratio > 4:1. When current pricing for Dysport (£164.74/500 units) and BOTOX (£128.93/100 units) is applied, incremental costs of £66.68/patient and £5.90/patient were incurred with Dysport for cervical dystonia and blepharospasm respectively. CONCLUSION: Results demonstrate that no one ratio exists between Dysport and BOTOX, consistent with the UK labeling: units of different serotype-A toxins are not interchangeable and comparisons based on simple dosage conversion factors are not applicable. Current pricing suggests incremental cost savings with BOTOX, other outcomes, including adverse events, also should be considered to better understand the overall costs and consequences of treatment.