|
A New Zealand standardised
formulation is available Formula
and Batch Sheet
This formula uses Ora-Blend/SF or Ora-Plus and Ora-Sweet/SF; 1:1, and
has been approved by the Extemporaneous Compounding Pharmacists' Group.
Alternatives are given below.
Levodopa/carbidopa solution, with the addition of ascorbic
acid, has been used to control severe fluctuations in patients with Parkinson's
Disease. The preparation is also known as LCAS. Patients drink the solution
and can titrate the dose to effect. The addition of ascorbic acid improves
stability such that solutions can be prepared on a daily basis by the
patient or caregiver.
The method described by Kurth et al is as follows:-
Mix 10 tablets of either carbidopa 10 mg/levodopa 100 mg, or carbidopa
25 mg/levodopa 100 mg (equivalent to 1000 mg levodopa), 2 g of ascorbic
acid, and 1000 mL of water.
Rotate or shake the container gently until the tablets dissolve. Crushing
the tablets is not usually necessary as they disperse easily.
The final concentration will be carbidopa 0.1 mg/mL and levodopa 1 mg/mL
or carbidopa 0.25 mg/mL and levodopa 1 mg/mL and ascorbic acid 2 mg /mL.
The solution was reported to be stable for 24-48 hours if refrigerated.1
Levodopa/carbidopa is also stable
in Ora-Plus/Ora-Sweet. 2
References
1. Kurth MC, Tetrud JW, Irwin I, Lyness WH, Langston JW. Oral levodopa/carbidopa
solution versus tablets in Parkinson's patients with severe fluctuations:
a pilot study. Neurology 1993 May;43(5):1036-9 [PubMed]
2. Nahata MC, Morosco RS, Leguire
LE. Development of two stable oral suspensions of levodopa-carbidopa for
children with amblyopia. J Pediatr Ophthalmol Strabismus 2000 Nov-Dec;37(6):333-7
PubMed
|