this is well explained in an article described a little farther down.
and it ain't easy with oral l-dopa and i don't see anyone posting here with advanced pd reporting great results taking only an extended released agonist or the neupro patch, anecdotally have heard the patch is better for some people.
so knowing that fluctuating l-dopa causes biochemical/transcription changes which might have a negative affect for hours/days, i'd say it is worth trying to achieve a consistant l-dopa level. that seems more art than science but duodopa shows that "quality" is more important than "quantity" with l-dopa. think about it, you pump the carbidopa/levodopa into your intestine, not your blood, you on average improve your "on" time and reduce dyskensia. the only difference between duodopa and oral meds is oral has to pass thru the stomach and duodopa doesn't and consistant dosing.
i don't have dyskinesia but i certainly wear off and am way beyond the "honeymoon" stage and am still playing around with doseages of immediate release and controlled release.
so if one has to take 50mg/hr for quality of life, possibly dissolving in ginger ale to speed delivery, then maybe you might have to do that. the 100mgIR/200mgCR combo makes sense since the CR is less than 70% bioavailable and therefore you could be getting 120mg of l-dopa and it takes longer to get into your bloodstream. i've read CR lasts longer if taken with food, i believe it's in the insert.
IMPAX LABS will be getting their l-dopa tablet approved which is supposed to be as good as STALVO, hopefully better because it is a combo of immediate and controlled release l-dopa.
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http://www.touchbriefings.com/pdf/2264/Mouradian.pdf
here's interesting discussion of duodopa infusion which is given to patients where oral l-dopa just isn't working well, either too much off time and/or dyskinesia.
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i found the following observations very interesting:
Abruptly switching back to intermittent
therapy does not revert the patients to their baseline
severity of motor fluctuations. Rather, a relatively
smooth motor response is enjoyed for at least several
more days until the beneficial effect of continuous
therapy eventually dissipates. The latter observation
suggests that continuous therapy had produced
plastic changes in the basal ganglia, which lasted
well beyond the removal of the physiologic
stimulation and re-introduction of intermittent
therapy. The advantages of continuous dopaminergic
therapy in PD can be gained in both early
and advanced disease where fluctuations can be
ameliorated both by stabilising circulating drug levels
and by normalising some of the central
pharmacodynamic alterations attending chronic,
non-physiologic, intermittent stimulation
2. Clinical experience
has shown that L-dopa given to non-parkinsonian
patients produces no dyskinesias in the absence
of nigral neuronal degeneration.
3. With advancing PD, as the number of dopamineproducing
nigral neurons decrease from about 50%
at the onset of symptoms down to about 20% or
less, striatal dopaminoceptive medium spiny
neurons become increasingly exposed to the
fluctuations in plasma and brain levels of L-dopa
and, hence, dopamine. The presence of a normal
complement of nigral dopaminergic neurons in
non-parkinsonian individuals shields the striatum
from oscillating L-dopa levels.
4. With advancing disease, as more and more neurons
disappear and the capacity to store dopamine and
release it tonically is diminished, standard
intermittent oral therapy with anti-parkinsonian
agents with a relatively short half-life, such as Ldopa,
result in oscillations in striatal intrasynaptic
dopamine levels that mirror the oscillations in
plasma. A neurotransmitter system that is designed
to function normally tonically is replaced with an
artificially pulsatile system. This non-physiologic
situation is believed to underlie the altered
pharmacodynamics of the L-dopa response.
Biochemical and molecular aberrations have been
documented in experimental models as a result of
intermittent stimulation of the nigrostriatal
dopaminergic system.
5. drug delivery such as with intravenous infusion of Ldopa.
Abruptly switching back to intermittent
therapy does not revert the patients to their baseline
severity of motor fluctuations. Rather, a relatively
smooth motor response is enjoyed for at least several
more days until the beneficial effect of continuous
therapy eventually dissipates. The latter observation
suggests that continuous therapy had produced
plastic changes in the basal ganglia, which lasted
well beyond the removal of the physiologic
stimulation and re-introduction of intermittent
therapy. The advantages of continuous dopaminergic
therapy in PD can be gained in both early
and advanced disease where fluctuations can be
ameliorated both by stabilising circulating drug levels
and by normalising some of the central
pharmacodynamic alterations attending chronic,
non-physiologic, intermittent stimulation