Medication-induced movement disorders (MIMD) result from the use of antipsychotic medications and manifest as various physical symptoms such as tremors and dystonia. The risk of developing these disorders varies with factors like age, type of drug, and dosage, with a notable incidence in young populations. Effective management includes prevention through careful prescription and monitoring, as well as utilizing treatment strategies for various specific movement disorders.

1. MEDICATION-INDUCED
MOVEMENT DISORDERS
OLADAPO SAMSON OLUWABUKOLA
9TH JULY, 2012

2. Definition of terms
 Medication-induced movement disorder (Extra-
Pyramidal Side Effects, EPSE) occurs due to treatment
with antipsychotic medications.
 It can also be defined as physical symptoms, including
tremor, slurred
speech, akathesia, dystonia, anxiety, distress, paranoia, an
d bradyphrenia, that are primarily associated with improper
dosing of or unusual reactions to neuroleptic (antipsychotic)
medications.
 Though they are commonly caused by the typical
antipsychotics, but can also be caused by the atypical.
 The adverse consequences of these syndromes can be
minimized by vigilant clinicians who systematically examine
patients at risk for these disorders and who manage them
properly when discovered.
 The best management is, of course, prevention, which
starts with the judicious prescription of neuroleptics, and an
awareness of the potential for certain nonpsychiatric

3. Incidence
 Though the true incidence and prevalence of drug-
induced movement disorders is unknown and likely
vastly underappreciated because of lack of
recognition, but studies and epidemiological evidence
have shown that one in 500 people who take
metoclopramide are likely to develop Extra-Pyramidal
Side Effects (EPSE). The risk for the development of
EPSE is highest in infants and children and adults
younger than 30 years of age. The risk of developing
EPS or Tardive Dyskinesia ,TD and the likely
irreversibility of TD are related to the length of
exposure and total accumulative exposure to the
drug.

4. Incidence
 Other factors influencing the correlation of Medication
induced Movement Disorder, MIMD and the use of
antipsychotic drugs include:
 age of the population,
 the drug being used and the dose,
 the definition of the movement being employed in
the study,
 design of the study.
 MIMD related to exposure to antipsychotic drugs is
estimated to occur in 19% and 42% of patients
receiving atypical (second-generation) and typical
(first-generation) antipsychotic drugs, respectively.

5. Risk Factors
 This is a function of the exposure and the dosage of
antipsychotics taken.
 The following populations are considered to be at
increased risk of Medication Induced Movement
Disorder.
Populations at High Risk for Developing Potential Reasons
MIMD
Elderly Decreased functional reserve
Elderly women Decreased Estrogen levels
Patients who have used Dopamine Receptor Increased exposure to DRBDs
Blocking Drugs, DRBDs for more than 3 months
Diabetics, independent of their use of DRBD, Impaired glucose metabolism
although the risk increases with the use of
DRBD
Persons with phenylketonuria Increased level of

6. Etiology
 The etiology of Medication Induced
Movement Disorders, MIMD, is largely of
biological origin:

7. Etiology – Biological
 The most common antipsychotic associated with EPSE is
haloperidol used especially in schizophrenia.
 Other antidopaminergic drugs like the antiemetic such as
metoclopramide or the tricyclic antidepressant
amoxapine can also cause extrapyramidal side-effects.
 Another common cause are Selective Serotonic Reuptake
Inhibitors (SSRIs), which decrease dopamine and
norepinephrine neurotransmission in the Substantia Nigra.
 Others include:
 Perphenazine (Trilafon)
 Thiothixene HCl (Navane)
 Fluphenazine HCl (Prolixin)
 Trifluoperazine (Stelazine)
 Risperidone (Risperdal)

8. Pathogenesis
 Extrapyramidal system, EPS: collateral
pathways separate from the pyramidal tract; plays
a role in voluntary movement whereas the
pyramidal tract is the motor areas of the cerebral
cortex to the anterior motor neurons of the spinal
cord
 The extra-pyramidal system includes all
descending motor tracts other than corticospinal
and corticobulbar tracts. Nerve impulses along
this pathway follow a complex, polysynaptic circuit
that involves the motor cortex, basal nuclei, limbic
system, thalamus, cerebellum, reticular formation
and nuclei in the brainstem
 EPS is contained in basal ganglia where both
Neurotransmitters that act on EPS include the following:
sensory and motor information travels; information
is integrated GABA relayed through thalamus to
Inhibitory and
Glutamate
spinal cord.
Acetylcholine
Serotonin
Dopamine

9. Pathophysiology
 Though the pathophysiology of MIMD has not been
clearly elucidated yet, but certain theories and
hypothesis suggest the interplay between:
 genetic predisposition,
 dopaminergic system hypersensitivity in the basal
ganglia,
 decreased functional reserve, and
 over activation of the cholinergic system.

10.  Postsynaptic Dopamine Receptor Hypersensitivity
Theory
 The chronic blocking of presynaptic dopamine receptors
enhances excitatory glutamatergic neurotransmission.
The neurotoxic stress in the striatum, which is caused by
increasing glutamate release and extracellular glutamate
levels at corticostriatal terminals, ultimately destroys the
output neurons, leading to dopaminergic hypersensitivity.
Although this theory has been the long-held hypothesis
as the cause of MIMD, it cannot completely account for
the clinical findings, primarily because it does explain the
fact that MIMD are not a universal phenomenon among
people exposed to Dopamine Receptor Blocking Drugs,
DRBDs

11.  Neurotoxicity Theory
 Suggests that MIMD are caused by the neurotoxic effects of
free radicals that are created as a byproduct of catecholamine
metabolism because the use of DRBDs increases the
turnover of neurotransmitters and because the basal ganglia
are particularly vulnerable to the effects of membrane lipid
peroxidation.
 Dopamine-GABA Hypothesis
 Dopamine has both inhibitory and excitatory effects on GABA
neurons, determined by the location and type of the dopamine
receptors in the brain. In this theory, which does not disregard
the fact that dopamine receptors become increasingly
sensitive to the effects of DRBD, the interaction between the
dopamine and gamma-aminobutyric acid (GABA) neurons
plays a greater role, likely accounting for the different, yet
simultaneous, effects of the DRBD. Unfortunately, this theory
has not been able to be converted into a treatment paradigm
because of the toxicity of the agents

12. Clinical Features
 Though the presentation of the MIMD is in no way different from
movement disorder secondary to neurological diseases
affecting the extrapyramidal motor system. Generally, based on
the features, there are 3 main groups:
 Drug induced movement disorders, such as:
akathisia, akinesia, hyperkinesia, dyskinesias, extrapyramidal
syndrome, and tardive dyskinesia
 Movement disorders secondary to neurological diseases
affecting the extrapyramidal motor system, such as:
athetosis, chorea, dystonia, hemiballismus, myoclonus, tremo
r, tics and spasm
 Abnormal movements in psychiatric disorders, such as:
mannerism, stereotyped behaviour and psychomotor
retardation.
 It is of importance that the presentation of each of this disorders
be distinguished, based on their phenomena, which is believed
to be of help to the medical fraternity in other to make quick

13. Akathisia
 Akathisia is a state of motor restlessness ranging from a
feeling of inner disquiet to inability to sit still or lie quietly.
It’s subjective feeling of objective signs of muscle unrest,
particularly in the lower extremities.
 Complaints of restlessness accompanied by movements
such as fidgeting of the legs, rocking from foot to foot,
pacing, or inability to sit or stand. Symptoms can develop
within a few weeks of starting or raising the dose of
traditional neuroleptic medications or of reducing the dose
of medication used to treat extrapyramidal symptoms.
 Difficulty remaining seated, agitation, restlessness ‡
Difficult to recognize and may be misdiagnosed with a
psychiatric disorder ‡ Can be treated with anti-
parkinsonian agents in addition to benzodiazepines

14. Rigidity - Akinesia
 Rigidity develops without tremor in many patients. When a rigid joint is
moved, sudden, rhythmic jerks due to variations in the intensity of the
rigidity occur, producing a ratchet-like effect (cogwheel rigidity)
 Akinesia is a state of motor inhibition or reduced voluntary movement.
It is also known to be the absence, poverty, or loss of control of
voluntary muscle movements.
 Slow movements (bradykinesia) are typical as rigidity progresses.
Movement also becomes decreased (hypokinesia) and difficult to
initiate (akinesia)
 Rigidity and hypokinesia may contribute to muscular aches and
sensations of fatigue. The face becomes masklike – definitive sign of
Parkinson’s Disease , with an open mouth, drooling, and reduced
blinking.
 Patient may appear depressed because facial expression is lacking
and movements are decreased and slowed.
 Speech becomes hypophonic, with characteristic monotonous,
stuttering dysarthria.
 Hypokinesia and impaired control of distal musculature cause
micrographia (writing in very small letters and makes activities of daily
living increasingly difficult.

15. Dystonia
 Dystonia can be defined as dyskinetic movements due to disordered
tonicity of muscle.
 It is sustained involuntary muscle contractions, often distorting body
posture. It can be primary or secondary, and often can be generalized,
focal or segmental. Diagnosis is clinical. Treatment of generalized
dystonia is often with combination of anticholinergics, muscle relaxants,
and benzodiazepines. Treatment of focal or segmental dystonia is often
with botulinum toxin; more generalized or refractory cases may benefit
from surgery.
 Tonic muscular contractions localized to one or several muscle groups,
particularly in the eyes, mouth, throat or neck.‡ Eye manifestations
include spasm of extra ocular muscles (oculogyric crisis). Neck
manifestations include torticollis. Back manifestations include
opisthotonus.‡ Pharyngeal muscle spasm or laryngospasm can be life-
threatening.‡ Can be treated with diphenhydramine or
benztropine (Cogentin) which are anti-parkinsonian agents
 Common drug causes of dystonia: Phenothiazines, Thioxanthenes,

16. Parkinsonism
 Parkinsonism refers to symptoms that are similar to those of Parkinson’s Disease but
caused by another condition.
 Signs and symptoms include:
 Resting tremor of one hand, maximum at rest. It is often the first symptom
 Rigidity
 Slow movements
 Postural instability
 Dementia
 Sleep disorders are common. Insomnia may result from nocturia or from the inability
to turn in bed
 Seborrheic dermatitis
 The mechanism is blockage of or interference with dopamine’s action in the basal
ganglia. The most common cause is ingestion of drugs that block dopamine receptors.
Such drugs include:
 Phenothiazines
 Thioxanthenes
 Butyrophenones
 Antipsychotics – can cause reversible parkinsonism
 Reserpine
 Metoclopramide – can be dose dependent or related to the patient’s susceptibility
(risk factors include older age and elderly women)
 Meperidine analoge – can cause sudden, irreversible parkinsonism. This occurs in IV
drug users.

17. Tardive Dyskinesia
 Tardive dyskinesia is a syndrome of abnormal
involuntary muscle movements resulting from
prolonged neuroleptic exposure. The syndrome may
arise either during or following the cessation of long-
term neuroleptic therapy. Raising the dose of
neuroleptics suppress the movement disorder acutely,
while lowering the dose results in an exacerbation of
the movements acutely.
 Known to manifest itself by oral buccal dyskinetic
movements including chewing movements, protrusion
of the tongue, lip smacking, puckering, and pursing
the lips, but it can consist of any hyperkinetic
movement disorder of any part of the body, including
the choreiform movements of the hands and feet,
axial symptoms of pelvic thrusting, or even dyskinesia

18. Tardive Dyskinesia - Pathophysiology
 The dopamine supersensitivy hypothesis of tardive
dyskinesia states that the hyperkinetic movements of
TD result from a super-sensitivity of the dopamine
receptor population in the striatum that is due to
chronic dopamine receptor blockade. This is justifies
the reason, why, TD improves acutely after increase in
dosage of neuroleptics, and why it is transiently
exacerbated by withdrawal of neuroleptics.
 The dopaine-acetycholine balance theory explicates
why anticholinergics exacerbate TD that is improved
by cholinergics.
 The GABA hypothesis explains some of the preclinical
subtleties of TD better than the older hypothesis but is
not as yet more clinically useful.

19. Other forms of Tardive movement
disorders
 Tardive dystonia – a less common form of MIMD resulting
from prolonged exposure to neuroleptics than tardive
dyskinesia, but tend to be more disabling. The symptoms
include the developemnt of dystonic movements following
prolonged neuroleptc exposure, primarily involving the
face and neck and especially producing retrocollis -
spasmodic torticollis in which the head is drawn back.
Estimated prevalence among the psychiatric patients vary
widely between 1.5% and 21%. Tardive dystonia differs
from tardive dyskinesia not only in being more
disabling, but in being less likely to remit.
 Tardive akathisia – generally associated with tardive
dyskinesia and often responds well to treatment with
dopamine depleting agents such as reserpine and
tetrabenazine.
 Other forms of tardive movment disorders, though
rare, includes Gilles de la Tourette’s syndrome, tardive
myoclonus, and tardive tremor

20. Differential Diagnosis
 For the sake of simplicity, it is explicit to describe the
differential diagnosis under the following heading:
 Medical
 Psychiatric

21. Differential diagnosis – Medical
 Parkinson’s Disease
 Benign childhood epilepsy
 Chorea Gravidarum
 Chorea in Adults
 Complex partial seizures
 Frontal lobe epilepsy
 Cortical Basal Ganglionic Disorder
 Wilson disease
 Huntington Disease dementia
 Tetanus
 Wilson Disease.
 Thyroid dysfunction
 SLE
 Polycythemia Rubra Vera

22. Differential diagnosis – psychiatric
 Dopamine-responsive dystonia
 Psychogenic Nonepileptic Seizures
 Alcohol related psychosis
 Mania
 Stimulant drug intoxication
 Drug withdrawal
 Agitated emotional state
One must be wary of missing akathisia, as it may be the cause for a
paradoxical worsening of behavior in response to antipsychotic
treatment. Equally important is the consideration of akathisia as a
driving force for agitation in demented patients who receive
antipsychotic drugs for psychiatric aspects of their dementias. If the
response to an antipsychotic is worsened behavior, akathisia
must be considered. Because the patients are often unable to
communicate, a high index of suspicion must be maintained. Restless
legs (Ekbom syndrome) is not associated with dopamine blockade
although it is relieved by L-DOPA and dopamine agonists. Patients
develop uncomfortable sensations in their legs that are relieved by
walking. These sensations occur primarily at night and interfere with
falling asleep but do not occur to a significant degree during the day.
This syndrome has been associated with iron deficiency in some
cases. Finally, tardive dyskinesia or "pseudo akathisia" can cause a
constellation of fidgety looking choreic movement in which patients

23. Investigations
 Investigations and workup may include selected laboratory
studies, as well as imaging modalities such as CT scan,
MRI, or Positron Emission Tomography (PET).
 Tardive blepharospasm should be evaluated with
electroencephalography (EEG) and a complete
ophthalmologic evaluation, including slit-lamp examination
to rule out the Kayser-Fleischer rings of Wilson disease.
 In addition, the following tests may be appropriate:
 Thyroid function tests to exclude thyroid dysfunction
 Serum biochemistry, serum copper, serum ceruloplasmin,
thyroid function tests, and syphilis serology to evaluate tardive
blepharospasm
 Connective tissue disease screening tests to exclude
systemic lupus erythematosus and other vasculitides
 Red blood cell (RBC) counts to exclude polycythemia rubra
vera
 Serum calcium level

24. DSM IV Criteria for MIMDs
 333.92 – Neuroleptic Malignant Syndrome
 Severe muscle rigidity, elevated temperature, and other related
findings (e.g. diaphoresis, dysphagia, incontinence, changes in level
of consciousness ranging from confusion to coma, mutism, elevated
or labile blood pressure, elevated creatine phosphokinase [CPK])
developing in association with the use of neuroleptic medication
 333.7 – Neuroleptic-induced Acute Dystonia
 Abnormal positioning or spasm of the muscles of the head, neck,
limbs, or trunk developing within a few days of starting or raising the
dose of a neuroleptic medication.
 333.99 – Neuroleptic-induced Acute Akathisia
 Subjective complaints of restlessness accompanied by observed
movements (e.g. fidgety movements of the legs, rocking from food
to food, pacing, or inability to sit or stand still) developing within a
few weeks of starting or raising the dose of a neuroleptic medication
(or after reducing a medication to treat extrapyramidal symptoms).

25. DSM IV Criteria for MIMDs cont’d
 333.82 – Neuroleptic-induced Tardive Dyskinesia
 Involuntary choreiform athetoid, or rhythmic movements
(lasting at least a few weeks) of the tongue, jaw, or
extremities developing in association with the use of
neuroleptic medication for at least a few months (may be
for a shorter period of time in elderly persons)
 333.1 – Medication-Induced Postural Tremor
 Fine tremor occurring during attempts to maintain a
posture that develops in association with the use of
medication(e.g. lithium, antidepressants, valporate)

26. DSM IV Criteria for MIMDs cont’d
 333.90 – Medication-induced Movement Disorder
Not Otherwise Specified – this category is for
Medication –Induced Movement Disorders not
classified by any of the specific disorders listed above.
Examples include:
 Parkinsonism, Acute Akathisia, Acute Dystonia, or
Dyskinetic movement that is associated with a
medication other than a neuroleptic
 A presentation that resembles neuroleptic malignant
syndrome that is associatied with a meidcationother than
a neuroleptic
 Tardive dystonia

27. Treatment
 Treatment modality of MIMD will be discussed under
the following headlines:
 Biological
 psychological

28. Treatment - Biological
 Management of drug-induced movement disorders in the older
patient requires careful consideration of the contraindications
imposed by such agents as anticholinergics and -blockers. At
present, the use of second-generation antipsychotics such as
clozapine, risperidone, olanzapine or quetiapine for reducing the
risk of treatment-emergent movement disorders in the elderly have
not been published. However, open-label studies of atypical
antipsychotics demonstrate a markedly lower incidence of both
EPSE and TD compared with conventional antipsychotic treatment
in the elderly.
 Dopamine-depleting agents: the most effective medications are
those that deplete catecholamines (eg, reserpine, tetrabenazine).
 Atypical antipsychotics (eg, clozapine, risperidone, olanzapine)
bind to dopamine D2 receptors and may improve tardive dystonia
when lower doses are used. Recent trials have shown that they not
only may cause or aggravate tardive dystonia but ultimately may
prove to be highly useful therapeutic agents to treat dystonias.
Long-term safety is not fully established for this indication.

29. Treatment – Psychological
 Patients frequently experience adverse effects of
antipsychotics before clinical improvements of
psychotic symptoms.
 High potency drugs are more likely to cause EPSE
which can render a patient to poor compliance of
taking drugs.
 Hence start management of EPS by giving pre-
information to patients about the drug, possible
side effects, duration, costs, and ways to minimize
these adverse effects.

30. Prognosis - overall
 The prognosis of patients with tardive dystonia is very poor.
Unfortunately, once developed, this condition is usually
persistent.
 The discontinuation of all dopamine receptor antagonists appears to
be the most important factor related to remission; patients who
permanently discontinue these agents increase their chance of
remission 4-fold compared with those patients who do not.
 Another factor related to remission is the total duration of dopamine
receptor antagonist therapy; patients taking dopamine receptor
antagonists for less than 10 years have a 5-times higher chance of
remission than those with more than 10 years of exposure.
 Tardive dystonia is most likely permanent in patients who continue
using neuroleptic drugs for more than 10 years.
 The indication for long-term use of neuroleptic agents must be well
established. Patients must be evaluated repeatedly in hopes of early
detection of tardive dystonia; once tardive dystonia is present, the
causative drug should be withdrawn if possible. If the patient is not
disabled by dyskinesia, observing and hoping for a spontaneous
recovery, rather than treating, is best.

31. Prognosis
 Patients who have previously experienced episodes of
neuroleptic malignant syndrome are at risk for recurrences. The
risk of neuroleptic malignant syndrome recurrence is strongly
related to the elapsed time between an episode of neuroleptic
malignant syndrome and restarting antipsychotics. If patients
are rechallenged with antipsychotics within 2 weeks of an
episode of neuroleptic malignant syndrome, 63% will have a
recurrence. If more than 2 weeks has elapsed, only 30% will
have a recurrence.
 87% of patients who develop neuroleptic malignant syndrome
will be able to tolerate another antipsychotic at some point in the
future, which is very important because most patients taking
neuroleptics require them to maintain a reasonable functional
status. Current practice is to switch to a different class of
antipsychotic when reintroducing these medications. Often, one
of the newer atypical antipsychotics is chosen because current
evidence suggests a lower incidence of neuroleptic malignant

32. Prevention
 Movement disorders may be aggravated by the administration
of dopamine-receptor blocking drugs. In vulnerable patients, the
administration of even a single dose of a dopamine-receptor
blocking drug may lead to incapacitating movement disorders.
 Patients with developmental disabilities, fetal alcohol syndrome,
schizophrenia, and other neuropsychiatric disorders may be
exquisitely vulnerable to TD upon exposure to dopamine-
receptor blocking drugs. If a patient exhibits a movement
disorder when given a drug, discontinuance of the
causative drug is generally wise. Advise the patient to avoid
receiving dopamine-receptor blocking drugs and warn against
the administration of these drugs.
 In addition, advise all of the clinicians treating the patient to
refrain from administering dopamine-receptor blocking drugs.
Advise the patient to obtain a medical alert bracelet warning
against the administration of dopamine-receptor blocking drugs.

33. References
 http://www.ncbi.nlm.nih.gov/pubmed/6627043
 http://www.extrapyramidalsideeffects.com/
 http://pediatrics.uchicago.edu/chiefs/documents/ExtrapyramidalSid
eEffects.pdf
 http://www.medmerits.com/index.php/article/acute_drug_induced_
movement_disorders/P8
 http://med.brown.edu/neurology/articles/sr55693.pdf
 http://emedicine.medscape.com/article/1151826-overview#a7
 http://books.google.com/books?id=w_HajjMnjxwC&pg=PA735&lpg=
PA735&dq=DSM+IV+333.99+criteria&source=bl&ots=i7PQbobJ1I&
sig=bhwZwRtb6Mggd7sLyYozgbKpjLE&hl=en&sa=X&ei=Ceb5T_av
EcL40gHv5YGEBw&ved=0CEwQ6AEwAw#v=onepage&q&f=false
 http://emedicine.medscape.com/article/288482-followup#a2650
 Treatment of Extrapyramidal Side Effects of Antipsychotics
Drugs, Frank. A Dept of Psychiatry MUCHS