ON LIVING WITH PARKINSON’S
ADDING AMANTADINE
Amantadine, which works on the glutamate (another brain chemical) pathway, is
commonly used to lessen the severity of
dyskinesia. (This drug began as a flu medication and gained approval for PD after it
unexpectedly eased Parkinson’s symptoms
and dyskinesia.)
REFERRING FOR DEEP BRAIN
STIMULATION (DBS)
DBS typically works best for people who
still get a good response to levodopa but
experience complications, such as dyskinesia and significant motor fluctuations
(“off ” periods). Surgery usually allows
for medication reduction, which limits
dyskinesia. Not everyone is a candidate.
Check out my recent “Ask the MD” video
on DBS at michaeljfox.org/ask-the-md.
New Therapies Are in Development
for Dyskinesia
Researchers, including several funded by
MJFF, are working in multiple areas to
develop better therapies to treat, and possibly even prevent, dyskinesia. Treatments
include drugs that modify brain chemicals other than dopamine and innovative
surgical techniques. Potential prevention
strategies center on improvements to the
current levodopa formulations. All of the
treatments discussed in this section are in
Phase II or Phase III clinical trials.
Three anti-dyskinesia medications, which
work on non-dopamine chemical pathways,
are in mid- to late-stages of clinical testing. Eltoprazine modifies serotonin levels,
while dipragulrant works on glutamate. An
extended-release preparation of amantadine (see above) also is in trials. This new
formulation is designed to achieve the highest medication levels in the morning and
afternoon — when it’s needed most — and
drop to lower concentrations in the evening,
when the potential side effect of insomnia
could interfere with medication benefit.
A surgical modality for dyskinesia in
research trials is focused ultrasound (FUS).
This procedure concentrates beams of
sound waves to destroy a small area of tissue in the brain (one of the same regions
targeted with DBS) while leaving other
areas of the brain relatively unharmed. It
doesn’t require a surgical incision, anesthesia, or the electrodes and battery that
DBS does. FUS is typically a one-time
procedure that takes effect immediately,
but it’s permanent and irreversible.
Novel formulations of levodopa, which
might lessen — and even prevent — dyskinesia are in the pipeline as well. The aim
of these preparations is to keep levodopa
concentrations more steady in the body
and brain. An “accordion” pill releases
medication slowly for better absorption and more consistent levels. Liquid
levodopa is infused continuously under
the skin through either a skin patch or a
device similar to an insulin pump.
Finding a balance between too little and
too much movement in advancing Parkinson’s can be challenging. Medication
adjustments (and DBS, in some cases) can
help, though, and therapies in development will potentially increase patients’
options. A wider variety of therapies
(and a potential solution) for dyskinesia
is just one of the ways MJFF is working
to improve the lives of people living with
Parkinson’s today.
Rachel Dolhun, MD, is a movement disorder
specialist and vice president of medical
communications at MJFF.
The medical information contained in this article is for
general information purposes only. The Michael J. Fox
Foundation has a policy of refraining from advocating,
endorsing or promoting any drug therapy, course
of treatment, or specific company or institution. It is
crucial that care and treatment decisions related to
Parkinson’s disease and any other medical condition
be made in consultation with a physician or other
qualified medical professional.
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