American Parkinson Disease Association, Washington Chapter

Acethylcholine: one of the major chemicals in the brain, a neurotransmitter that stimulates motor nerves.

Action tremors: tremors that increase with voluntary movements.

Agonist: a class of medication, which stimulates the dopamine receptors directly.

Akinesia: complete or partial loss of muscle movement.

Amantadine (Symmetrel): a medication initially designed to relieve influenza symptoms but later found to assist with rigidity and other parkinsonian symptoms. May also help to reduce dyskinesias.

Antidepressant (medication): medications used to treat depression.

Bilateral: occurring on both sides of the body (left and right).

Blepharospasm: rapid blinking or forced closure of the eyes.

Bradykinesias: poverty and slowness of movements.

Central nervous system: the brain and spinal cord.

Carbidopa: a drug used in combination with levodopa in the treatment of Parkinson's which prevents levodopa from being metabolized in the body, thus allowing more levodopa to reach the brain.

Cogwheeling: refers to increased muscular tone. Regular jerky quality in response to passive movements as if there was a cogged wheel in the joint.

Chorea: rapid, jerky, dance-like movements of the body. Dementia: progressive deterioration of mental state.

Dopamine: a chemical produced by the brain; it assists in the effective transmission of electrochemical messages between neurons.

Dopamine agonists: Mimic the effects of dopamine without boosting body's production. This class of drugs is used to postpone levodopa therapy and its side effects.

Dyskinesias: abnormal, involuntary movements of voluntary muscles (may involve face, neck, hands, arms, legs, etc.) including twitches, jerks, twisting, or writhing movements.

Dysphagia: difficulty swallowing common in later stages of Parkinson's.

Dystonia: slow, twisting movements which may involve one limb or several limbs.

Essential tremors: a rapid tremor that, in contrast to the slower, resting tremors of Parkinson's, increases with activity.

Familial tremor: an inherited essential tremor.

Festinating gait: rapid, uncontrolled shuffling.

Flexion contracture: permanent bending of parts of the body.

Freezing: temporary, involuntary inability to move.

Haloperidol (Haldol): a tranquilizing medication that can cause Parkinson-like symptoms.

Idiopathic: of unknown cause.

Levodopa: antiparkinson drug which is changed into dopamine in the brain; usually combined with carbidopa i.e. Sinemet).

MAO-inhibitors: Enhance the effect of dopamine by interfering with its breakdown in the brain. May help prevent further damage to cells.

Micrographia: small handwriting; in Parkinson's, writing may start out normal size and become smaller and smaller. Sometimes an early symptom of Parkinson's.

Off dystonia: an abnormal posturing or cramping when levodopa levels are at their minimum in the bloodstream.

"Off" time: time during which antiparkinsonian medications are not working well and motor function is poor.

On-Off fluctuation: fluctuations in response to antiparkinsonian drugs in which patient changes suddenly 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 a sitting position to standing position).

Peak-dose dyskinesia: a type of dyskinesia which occurs when the dopamine in the brain is supposed to be at its peak; results from too much dopamine in the system.

Postural instability: Loss of balance and coordination. Inability to right oneself when falling down.

Propulsive gait: walking that is propelled forward.

Resting tremor: tremors of a limb when the body is relaxed.

Rigidity: increased resistance to passive movement of a limb.

Sialorrhea: drooling.

Substantia nigra: an area of the midbrain containing a cluster of black-pigmented nerve cells that produce dopamine.

Tremors: a rhythmic involuntary movement of a body part.

Wearing off: a fluctuation in response to antiparkinson medications when the medications are losing their effect and parkinsonian symptoms progressively appear. In other words; medication effects end before the next dose is due.