Table 1.
Calculating LD Equivalents From LD-Containing Medications.a
| Medication | Dose Multiplication Factor |
|---|---|
| Immediate-release LD, including enteral suspension | No adjustment needed (i.e., multiply by 1) |
| Sustained-release LD, controlled-release or prolonged-release | Multiply by 0.75 |
| Extended-release LD (Rytary®), mg | Multiply by: |
| 0 – 855 | 0.42 |
| 856 – 1755 | 0.48 |
| 1756 – 2340 | 0.56 |
| ≥ 2341 | 0.67 |
| If any COMT inhibitor is used, multiply sum of calculated LD equivalents from above by 1.33 | |
LD = levodopa. CD = carbidopa. IR = immediate release. COMT = catechol-O-methyltransferase.
Conversion factors provided are based on data from literature [31], [32] The LD dose contained in combined LD/CD/COMT-inhibitor formulations (e.g., Stalevo®) counts as IR and needs to be added to the LD equivalents from all other sources of LD before the sum is multiplied for the COMT-inhibitors correction factor (i.e., do not apply COMT correction factor until all LD equivalents are summed).
Reprinted from The Lancet Neurology, 21, Michael J Soileau, Jason Aldred, Kumar Budur, Nahome Fisseha, Victor SC Fung, Anna Jeong, Thomas E Kimber, Kevin Klos, Irene Litvan, Daniel O’Neill, Weining Z Robieson, Meredith A Spindler, David G Standaert, Saritha Talapala, Eleni Okeanis Vaou, Hui Zheng, Maurizio F Facheris, Robert A Hauser, Safety and efficacy of continuous subcutaneous foslevodopa-foscarbidopa in patients with advanced Parkinson’s disease: a randomised, double-blind, active-controlled, phase 3 trial, Pages 1099–1109, Copyright (2022), with permission from Elsevier [3].