We're going to talk now about drugs used to
treat other movement disorders or what we
call non-parkinsonian movement disorders.
We're going to start off first with tremor.
Now you're going to cover tremor much in
much more detail in your neurology lectures
I'm only going to talk about the
Propranolol is a beta blocker.
Other beta blockers can be used as well.
Propranolol is a very effective agent in
It seems to respond well to beta blockade,
we're not exactly sure why that happens.
Gabapentine, primidone and topiramate are
also anti-epileptic drugs that may also
work in postural tremor.
Huntington's disease is a complex,
choreiform type of movement.
It's inherited. It's passed on.
It affects the GABA function.
So by giving medications to affect GABA
function, we can reduce Huntington's disease.
These medications include those which
deplete the storage of dopamine or block
Vesicular monoamine transporter type 2
(VMAT) inhibitors, such as tetrabenazine and
deutetrabenazine, act by depleting dopamine
storage in presynaptic vesicles in CNS.
They should not be used if the patient also
has depression, agitation, or psychosis.
Antipsychotics work by blocking dopamine
The second-generation antipsychotics, such
as risperidone, are preferred over the
first-generation ones, such as haloperidol.
Benzodiazepines can be provided as needed.
Because these drugs interfere with dopamine,
the patient must be regularly monitored for
signs for parkinsonism.
In many Huntington disease patients, chorea
peaks at approximately 10 years after the
first signs of disease, followed by
declining choreiform activity while
bradykinesia and rigidity become more
prominent, so different therapies would then
be necessary. Tourette syndrome also
dopamine depletion or transmission blocking,
which means using VAMT2 inhibitors or
antipsychotics Alpha adrenergic agonists,
such as guanfacine and clonidine can be
useful. They are also used to treat
attention-deficit hyperactivity disorder
known as ADHD. The blood pressure must be monitored
because they cause hypotension.
Botulinum toxin injection is possible for
focal motor or phonic tics or if there are
violent neck extension tics.
In complex cases or comorbid epilepsy, other
drugs have been used, such as antiseizure
medications, like topiramate and
carbamazepine, as well as benzodiazepines and
cannabinoids. Wilson's disease.
Now, Wilson's disease is generally thought
that it was liver disease.
The classical finding in Wilson's disease is
a Kayser-Fleischer ring that's
seen in the eye on eye exams.
So you can see a little bit of a brown haze
on the edges of the iris.
This is a disorder of copper metabolism.
Why am I talking about it here?
Because it does result in neurological
Myasthenia can occur, and mild movement
disorders that are very nonspecific can
occur in Wilson's disease.
This is why, just as a clinical pearl,
always do a good eye exam in your patients
and take a close look at their iris, because
you may actually pick up Wilson's disease.
I've done it a couple of times in my own
The treatment is penicillamine.
Now, penicillamine chelates copper out of
So if you can give them penicillamine early
enough, you can actually treat the movement
disorder associated with Wilson's disease.
Restless leg syndrome is a common movement
disorder characterized by an uncomfortable
urge to move the legs during sleep or other
periods of inactivity, and which is relieved
by moving the legs.
The cause is unknown. In approximately 50%
of the cases there is a family
history of RLS.
Comorbid conditions which are commonly
associated include low iron stores, uremia,
neuropathy, spinal cord disease, and
The pathophysiology may involve reduced
central iron stores or alterations in
dopaminergic pathways and other
For treatment, iron supplementation is given
if the serum ferritin is less than 75
micrograms per liter, and/or if transferrin
saturation is less than 20 percent.
Alpha-2-delta calcium channel
ligands like gabapentin enacarbil and
pregabalin are considered first-line
therapies; they inhibit calcium mediated
neurotransmitter release, but their actual
role in RLS is unknown.
Dopamine agonists, such as pramipexole, ropinirole,
are effective in the treatment of RLS.
Carbamazepine (Tegretol) may also be
useful in the treatment. Opioids are reserved
for treatment of severe RLS but must be used
cautiously because of side effects
and potential for abuse.
Next we're going to talk about dystonia.
Dystonia refers to sustained or intermittent
muscle contractions, usually focal.
Examples include: retrocollis, torticollis,
opisthotonus, hyperextension of the arms or
legs, blepharospasm, and jaw dystonia.
Examples of opisthotonos and retrocollis are
shown in this slide.
There are many types and multiple causes of
dystonia; most are idiopathic, but they may
be acquired, as in certain CNS pathologies
or by certain drugs.
Inherited causes are rare.
The most prevalent form of dystonia is
idiopathic cervical dystonia.
The pathogenesis is uncertain, but two
mechanisms are suggested.
Abnormal dopaminergic activity in the basal
ganglia is likely, since dopamine receptor
antagonists such as antipsychotic drugs and
metoclopramide can cause dystonia.
Abnormal cholinergic activity is also a
strong possibility, since anticholinergic
therapy can be effective.
For the treatment of acute drug-induced
dystonia in adults: stop or change the drug
and give anticholinergics, such as
trihexyphenidyl or benztropine.
For other dystonias in adults, if it is
drug-induced when it also called “tardive
dystonia,” although some authors consider it
a type of tardive dyskinesia: Stop or change
the drug if possible.
For the remaining types of dystonias, a
trial of levodopa should be tried, to exclude
a rare dopa-responsive dystonia.
Botulinum toxin injection is the preferred
If that is not possible, or if there is not
a good response, the benzodiazepines and
anticholinergics are used.
Other medications which may be employed
include baclofen, which activates the
GABA-beta receptor, thereby inhibiting the
release of excitatory neurotransmitters.
A vesicular monoamine transporter type 2
inhibitor such as tetrabenazine may be given
if there is generalized isolated dystonia.
Finally, deep brain stimulation if the
dystonia is refractory to other
treatments. Next up we're going to move on
to tardive dyskinesia.
Tardive dyskinesia, or TD, is a drug-induced
hyperkinetic movement disorder,
usually occurring in orofacial muscles,
associated with the use of
dopamine-receptor-blocking agents, such as
first-generation ones, or anti-emetics, such
as metoclopramide or
The most important risk factors are older age
and length of drug use; TD developed in a
about half of the patients who took a
first-generation antipsychotic for 10 years.
Other risk factors are people with fetal
alcohol syndrome, other brain disorders, and
diabetics. Women are more affected than men.
The pathophysiology of TD is not understood,
but possible mechanisms include chronic
blockade or damage of D2 receptors, which
causes increased levels of glutamate in the
striatum, with consequent excitotoxic
destruction of GABA- and peptide-containing
neurons. Another possible mechanism involves
the production of free radicals which are
generated by increased neuronal dopamine
For the prevention of tardive dyskinesia,
use the lowest effective dose of
Screen for TD every 6 months sing the
Abnormal Involuntary Movement Scale (AIMS)*
because TD may become irreversible.
For metoclopramide or prochlorperazine,
avoid continuous use for more than 12 weeks.
The treatment of TD involves discontinuing
the drug if possible, using a lower dose, or
switching to an anti-psychotic with lesser
risk for TD (e.g., risperidone,
For mild TD, benzodiazepines are advised,
while for moderate to severe TD, the
vesicular monoamine transporter type 2
inhibitors are indicated, such as
valbenazine, deutetrabenazine, and
tetrabenazine): these drugs deplete dopamine
storage in presynaptic vesicles in CNS.
Deep brain stimulation is recommended for
So there you have it. These are the
non-parkinsonian movement disorders.
I'm sure you'll do very well on your exams.