Ablation
Surgical destruction or removal of any part of the body.

Acetylcholine
A chemical messenger released by cholinergic nerves. Normally found in many parts of the body, including the brain, and necessary to normal body functioning. Medications that block the action of acetylcholine can help with the symptoms of Parkinson’s disease. There appears to be a reciprocal seesaw relationship between acetylcholine and dopamine and their respective nerve cell systems.

Action tremor
Rhythmic, involuntary movement of a limb when movement is initiated, e.g., when writing or lifting a cup. Not usually seen in the earlier stages of Parkinson's.

Adjunctive
Another treatment used together with the primary treatment. Its purpose is to assist the primary treatment.

Adrenaline (epinephrine)
The neurotransmitter of the adrenal gland that is secreted in moments of crisis. It stimulates the heart to beat faster and work harder, increases the flow of blood to the muscles, causes an increased alertness of mind, and produces other changes to prepare the body to meet an emergency. It is also a chemical messenger in the brain.

Agonist
A chemical or drug that mimics neurotransmitter activity. For example, a dopamine agonist used in the treatment of Parkinson’s disease "fools" the brain into thinking that it is dopamine and the brain responses with improvement in symptoms.

Akinesia
Absence or difficulty in producing of body movements.

Alpha-tocopherol
Chemical name for biologically active form of Vitamin E.

Amantadine
A drug that stimulates the release of available dopamine in the brain thereby improving symptoms. Also, amantidine can act on NMDA glutamate receptors in the brain that may help to reduce the involuntary movements (dyskinesia) sometimes associated with Parkinson’s disease treatments.

Anticholinergic
Adjective applied to a substance (medication) that reduces the action of acetylcholine.

Anticholinergic drugs (Artane, Cogentin)
The group of drugs that decreases the action of acetylcholine. The specified drugs may help reduce rigidity, tremor and drooling in Parkinson's.

Anticoagulant
A substance that prevents blood clotting.

Antihistamines
Drugs that oppose the actions of histamine; commonly used to treat allergies. Used in the past for Parkinson's as they sometimes had beneficial effects on symptoms due to their anticholinergic properties.

Apomorphine
A derivative of morphine and a dopamine agonist. Currently experimentally used as injectable treatment for severe Parkinson's.

Ataxia
Loss of balance.

Athetosis
Dyskinesias in which there are slow, repetitive, sinuous involuntary movements.

Atypical
Unusual; not conforming to type.

Autonomic nervous system
The branch of the nervous system that controls internal organs in the body, i.e., heart, lungs.

Basal ganglia or nuclei
Deep structures in the brain, concerned with normal movement and walking. The caudate nucleus, putamen, subthalamic nucleus and Substantia Nigra are basal ganglia affected in Parkinson's.

Benign essential tremor
A condition characterized by tremor of the hands, head, voice and sometimes other parts of the body. Essential tremor often runs in families and is sometimes called familial tremor. It is sometimes mistaken for a symptom of Parkinson’s. However, this is an action tremor and there is no rigidity or bradykinesia.

Beta-blockers (ß-blockers)
Drugs that block the action of epinephrine at certain sites. Usually used to treat hypertension and heart disease, they may be effective in the treatment of benign essential tremor.

Bilateral
Occurring on both sides of the body.

Bioavailability
Effectiveness; The degree to which a substance is absorbed and circulated in the body.

Blepharospasm
Spasmodic blinking or involuntary closing of the eyelids; a type of dystonia.

Bradykinesia
The slowing down and gradual loss of spontaneous movement. It is a major symptom of Parkinson's.

Bromocriptine (Parlodel)
A dopamine agonist useful in treating all of the primary symptoms of Parkinson's. It may be used alone or with other anti-Parkinson medications. This is an older-generation dopamine agonist that is less effective and has higher risks of side effects compared to newer dopamine agonists.

Carbidopa (Lodosyn)
The ingredient in Sinemet that prevents the breakdown of the levodopa in the body before it can reach the brain. Carbidopa helps levodopa to be more effective and can be used to reduce the side effects of levodopa and dopamine agonists.

Central nervous system (CNS)
The brain and spinal cord.

Cerebellum
The part of the brain that is involved in coordination.

Cerebral cortex
The largest part of the brain; responsible for thought, reasoning, memory, sensation and voluntary movement.

Chorea
A type of dyskinesia (abnormal movement), characterized by continuing, rapid, dance-like movements. May result from high doses of levodopa and/or long-term levodopa therapy.

Choreoathetosis
A dyskinesia characterized by choreic and athetoid movements.

Cognitive function
A person’s ability to perceive, reason and understand.

Cogwheel rigidity
Stiffness in the muscles, with a jerky quality when arm and leg joints are repeatedly moved.

COMT inhibitors
Drugs that block catechol-O-methyltransferase, an enzyme that breaks down dopamine.

Constipation
Diminished ability of intestinal muscles to move stool, often resulting in difficulty voiding or in very hard stool.

Deep brain stimulation (DBS)
A new surgical procedure that has proven to be very effective in treating Parkinson’s disease. The surgery includes the implantation of permanent electrodes in various parts of the brain through which continuous pulses of electricity are given. Further, the stimulation is adjustable. This surgery has largely replaced older types of surgery where specific areas of the brain were purposefully destroyed. DBS is safer and more effective than older, destructive surgeries. Targets for DBS include the subthalamic nucleus and globus pallidus. The thalamus also can be targeted but thalamic DBS is less effective.

Dementia
The loss of some intellectual abilities; characterized by loss of awareness, reality and confusion.

Deprenyl (Eldepryl, Selegiline, Jumex)

A drug that slows the breakdown of chemicals like dopamine by inhibiting the action of certain enzymes. It increases effects of dopamine in the brain. There is some data that this medication can help slow the progression of Parkinson’s disease early in the course of the illness, though this research is controversial.

Dopamine
A chemical produced by the brain; it assists in the effective transmission of messages from one nerve cell to the next. It is deficient in the basal ganglia and substantia nigra of a person with Parkinson's. It coordinates the actions of movement, balance and walking.

Dopamine Agonists
Drugs that mimic the effects of dopamine and stimulate the dopamine receptors.

Dopaminergic
An adjective used to describe a chemical, a drug or a drug effect related to dopamine.

Drug-induced Parkinsonism
Parkinson's symptoms brought on by drugs used to treat other conditions, e.g., neuroleptic drugs; metoclopramide, which is used to treat stomach problems; certain antidepressants such as amoxiapine and the SSRIs; and reserpine, used to be used to treat hypertension.

Dysarthria
Speech difficulties caused by the disturbance of the muscles associated with speech.

Dyskinesia
Abnormal movement of voluntary muscles. May appear as a side effect of long-term drug treatment in Parkinson's and may worsen in response to stress. (also see levodopa-induced dyskinesia)

Dysphasia
Difficulty in swallowing.

Dystonia
A movement disorder that commonly involves the head, neck and tongue. It can result in involuntary writing movements and unusual postures.

Electrocautery
A surgical treatment in which electric current is used to remove growths.

Encephalitis
Inflammation of the brain usually caused by a viral infection.

Essential tremor (ET)
A neurological disorder characterized by tremors. Areas affected most often include the hands, arms, head and sometimes the voice.

Ethopropazine (Parsidol/Parsitan)
A drug sometimes used in the past for Parkinson's due to its anticholinergic effects.

Extrapyramidal nervous system
Refers to the caudate, putamen, subthalamic nucleus and Substantia Nigra. It is affected in Parkinson's.

Festination
Walking in rapid, short, shuffling steps.

Flexion
A bent, curved posture.

Glaucoma
A sustained increase of pressure within the eyeball that can injure the optic nerve and cause impaired vision or blindness. Although rare, treatment with anticholinergics may exacerbate glaucoma.

Globus pallidus
The inner part of the basal ganglia.

Hydrolysis
The process of adding water to split a chemical compound.

Hypokinesia
Abnormally diminished motor activity.

Hypomania
A milder form of mania, which is a state often characterized by extreme excitement, elation, irritability and/or hyperactivity.

Idiopathic
An adjective meaning "of unknown cause." The usual form of Parkinson's is idiopathic Parkinson's.

Intention tremor
Tremor occurring when the person attempts voluntary movement.

Lenticular nucleus
This group of cells along with the caudate nucleus form the Striatum or Corpus Striatum.

Levodopa
The international generic name for the medicinal formulation of L-Dopa. It is contained in Sinemet and Prolopa.

Levodopa-induced dyskinesias
A side effect of medication that may occur with prolonged use. Reducing the amount of medication may alleviate these abnormal, involuntary movements. Modern approaches to medical therapy try to avoid or minimize the use of levodopa in order to reduce the risks of levodopa-induced dyskinesia.

Livido reticularis
A purplish or bluish coloration of the skin seen usually below the knee and on the forearm in persons treated with amantadine (Symmetrel). This is usually a benign condition.

Lodosyn (carbidopa)
The ingredient in Sinemet that prevents the breakdown of the levodopa in the body before it can reach the brain. Carbidopa helps levodopa to be more effective and can be used to reduce the side effects of levodopa and dopamine agonists.

Mirapex (pramipexole)
A new-generation dopamine agonist that is better tolerated and more effective.

Micrographia
The tendency to have very small handwriting due to difficulty with fine motor movements in Parkinson's.

MPTP
A toxic chemical, exposure to which may lead to Parkinsonism in intravenous drug abusers. It is now used to produce Parkinsonism in laboratory animals in order to study the disease.

Multiple sclerosis (MS)
A disease in which the body’s immune system mistakenly attacks normal tissues of the body. In MS, these attacks are aimed at the myelin in the central nervous system.

Myoclonus
Jerking, involuntary movement of arms and legs, usually occurring during sleep.

Neostriatum
Vital part of the brain comprised of two basal ganglia (caudate and putamen). These are part of the basal ganglia.

Neuroleptic drugs (Also called major tranquilizers)
A class of drugs that act as dopamine antagonists (by blocking some dopamine receptors). These medications are used in the treatment of serious psychiatric disorders. They can produce or aggravate symptoms of Parkinsonism. This class includes Haloperidol (Haldol) and the phenothiazines, e.g., Compazine, Stelazine, Chlorpromazine, etc.

Neuron
A nerve cell.

Neurotransmitter
A specialized chemical produced in nerve cells that permits the transmission of information between nerve cells .

Nigrostriatal degeneration
Degeneration of the nerve pathways from substantia nigra to the striatum.

Norepinephrine
Chemical transmitter found mainly in two areas of the brain involved in governing the involuntary autonomic nervous system.

On-off effect
Fluctuations that occur in response to levodopa therapy in which the person’s mobility changes suddenly and unpredictably from a good response (on) to a poor response (off).

Orthostatic hypotension
A drop in blood pressure during rapid changes in body position (e.g., from sitting to standing). This can produce dizziness or light-headedness.

Palilalia
A symptom of Parkinsonism, especially the postencephalitic form, in which a word or syllable is repeated and the flow of speech is interrupted.

Pallidectomy
Surgical procedure where the globus pallidus is separated to improve tremors, rigidity and bradykinesia. This type of surgery is rarely indicated and has been replaced by deep brain stimulation (DBS).

Pallidotomy
Surgery that permanently destroys the overactive globus pallidus to improve the symptoms of Parkinson's disease.

Paraesthesia
Sensations, usually unpleasant, arising spontaneously in a limb or other part of the body, experienced as "pins and needles" or a fluctuations of warmth or coldness (thermal paresthesias).

Parkinson's facies
A stoic, mask-like facial expression, with infrequent blinking that is characteristic of Parkinson's disease.

Parkinsonism
The term referring to the group of conditions characterized by the most typical symptoms: tremor, rigidity, bradykinesia, stooped posture and shuffling gait. The more common causes of Parkinsonism are Parkinson's disease, striatonigral degeneration and a reversible syndrome that is induced by certain drugs.

Paralysis agitans
The Latin form of the older, popular term "shaking palsy," which was used to designate early Parkinson's diagnosis.

Parlodel (bromocriptine)
A dopamine agonist useful in treating all of the primary symptoms of Parkinson's. It may be used alone or with other anti-Parkinson medications.

Pergolide (Permax)
A dopamine agonist. This is an older-generation dopamine agonist that is less effective and has higher risks of side effects compared to newer dopamine agonists.

Postural instability
Difficulty with balance.

Postural tremor
Tremor that increases when hands are stretched out in front.

Precursor
Something that precedes, e.g., Levodopa is a precursor to dopamine in that levodopa is converted to dopamine in the brain.

Progressive supranuclear palsy (PSP)
A degenerative brain disorder sometimes difficult to distinguish from Parkinson's especially in the early stages. PSP symptoms are rigidity and akinesia, difficulty looking up and down, speech and balance problems. Those with PSP often have poor response to antiparkinson medications.

Prolopa
Trade name for the anti-Parkinson drug composed of levodopa and benserazide. This drug combination contains a ratio of 4 mg. of levodopa to 1 mg. of benserazide (Prolopa 50-12.5, 100-25, 200-50).

Propulsive gait
Disturbance of gait typical of Parkinsonism in which, during walking, steps become faster and faster with progressively shorter steps that passes from a walking to a running pace and may precipitate falling forward.

Pseudobulbar palsy
A disorder that occurs in patients with arteriosclerosis that is often mistaken for Parkinson’s disease.

Range of motion
The extent that a joint will move from being fully straightened to completely bent.

Resting tremor
Shaking that occurs in a relaxed and supported limb.

Retropulsive gait
Walking that is propelled backwards.

Rigidity
Muscular stiffness that is common in people with Parkinson's disease. It is characterized by a resistance to movement in the limbs.

Requip (ropinirole )
A new generation dopamine agonist that is better tolerated and more effective.

Seborrhea
Increased oily discharge from the sebaceous glands of the skin in those with Parkinson’s.

Seborrheic dermatitis
Inflammation of the skin sometimes associated with seborrhea.

Shaking palsy
An older, popular term that was used to designate early Parkinson's diagnosis.

Shy-Drager Syndrome
A rare condition in which the symptoms are the result of abnormalities in motor function and problems in the autonomic nervous system. A person with Shy-Drager Syndrome has Parkinsonism, extremely low blood pressure that worsens upon standing, bladder problems, severe constipation and decreased sweating.

Sialorrhea
Drooling.

Sinemet
Trade name for the anti-Parkinson drug that is a mixture of levodopa and carbidopa. This drug combination contains a ratio of levodopa 4 mg. or 10 mg. to carbidopa 1 mg. (Sinemet 100/25, Sinemet 250/25).

Sinemet CR
Controlled-release Sinemet. A combination of levodopa and carbidopa in a capsule tablet contained in a matrix (outer layer) that releases the drug more slowly in the body.

These capsules are not to be taken all at once, but rather in separate doses over the course of a day.

Stereotactic headframe
A metallic frame bolted to a patient's head to prevent any movement during brain surgery that utilizes stereotactic methods.

Stereotactic surgery
Surgical technique that involves placing a small electrode in an area of the brain to destroy a tiny amount of brain tissue (see Deep Brain Stimulation).

Striatonigral degeneration
A degenerative disorder similar to idiopathic Parkinson’s disease in which there is a degeneration of the nerve pathways traveling from the striatum to the substantia nigra. People with this degeneration also appear to have Parkinsonism but respond differently to drug therapy.

Striatum
Area of brain basal ganglia that controls movement, balance and walking.

Subthalamic nucleus (STN)
A nerve center deep within the brain that controls many aspects of normal motor function. It may be targeted for deep brain stimulation to reduce symptoms of Parkinson's disease.

Sustention or postural tremor
Tremor that increases when hands are stretched out in front.

Supranuclear gaze palsy
A cerebral degenerative disorder in which patients develop paralysis of their eye movements.

Symmetrel (amantadine)
A drug that releases dopamine and is useful in PS.

Tardive dyskinesia
A movement disorder associated with long-term use of certain medications, such as the neuroleptic drugs Chlorpromazine, Haloperidol, Loxapine, etc. Movements of a person with tardive dyskinesia are similar in appearance to those of a person with levodopa-induced dyskinesias, but the causes of the two conditions are different.

Thalamotomy
Operation in which a small region of the thalamus is destroyed. Tremor and rigidity in Parkinsonism and other conditions may be relieved by thalamotomy. This surgery is rarely indicated and has been replaced by deep brain stimulation.

Thalamus
A mass of gray matter centrally placed deep in the brain near its base and serving as a major relay station for impulses traveling from the spinal cord and cerebellum to the cerebral cortex.

Toxin
A poisonous substance.

Tremor
Rhythmic shaking and involuntary movement of part(s) of the body as a result of muscle contractions.

Unilateral
Occurring on one side of the body. Parkinson's symptoms usually begin unilaterally.

Wearing-off effect
The tendency, following long-term levodopa treatment, for each dose of the drug to be effective for shorter periods of time.