Selegiline Health Dictionary

Parkinsonism, or paralysis agitans, is a progressive disease of insidious onset usually occurring in the second half of life; it is much more common in men than in women. Degenerative changes in the basal ganglia (see BASAL GANGLION) lead to a de?ciency in the NEUROTRANSMITTER, DOPAMINE – or occasionally in other neurotransmitters – and it is this de?ciency that is responsible for most cases.

The clinical picture is characterised by TREMOR, rigidity and poverty of spontaneous movements. The loss of natural play of expression in the face produces a mask-like expression. Rigidity of the larynx, tongue and lips produces a ?at, expressionless voice. The most common symptom is tremor, often affecting one hand, spreading to the leg on the same side, then to the other limbs. It is more pronounced in resting limbs and is exaggerated by excitement, stopping during sleep. It may interfere with eating and dressing. Limb rigidity leads to an increasing tendency to stoop. The patient has a shu?ing walk with a peculiar running gait.

Treatment Several drugs are used to keep the condition under control. None is curative, all have side-effects, and ?nding the most suitable one for any individual depends largely on understanding cooperation between family doctor and patient. Dopaminergic and antimuscarinic (see ANTIMUSCARINE) drugs are used in treatment. Levodopa, a precursor of dopamine, is a long-used example of the former; it produces spectacular improvement in one-?fth and moderate improvement in two-?fths of patients. Benzhexol hydrochloride is one of several antimuscarinic drugs used in Parkinson’s disease; selegiline is a monoamine-oxidase inhibitor used in severe parkinsonism in conjunction with levodopa to reduce ‘end-of-dose’ deterioration. Adverse effects include HYPOTENSION, nausea and vomiting, confusion, and agitation. Some drugs used to treat other disorders produce Parkinsonian side-effects. Patients seeking further advice and help, together with their relatives, are advised to contact the Parkinson’s Disease Society of the UK.... parkinsonism

(1) A muscle that works in concert with an AGONIST muscle to perform a certain movement.

(2) An agent, for example a drug, that acts with another to produce a result that is greater than adding together the separate effects of the two agents. Synergism in drug treatment may be bene?cial, as in the case of combined LEVODOPA and SELEGILINE, a selective monoamine oxidase inhibitor (see MONOAMINE OXIDASE INHIBITORS (MAOIS), in the treatment of PARKINSONISM. It may be potentially dangerous, however, as when MAOIs boost the effects of BARBITURATES.... synergist

(MAOI) a drug that prevents the activity of the enzyme *monoamine oxidase (MAO). MAO inhibitors include phenelzine, isocarboxazid, and tranylcypromine. These drugs are irreversible inhibitors of monoamine oxidase A, whose use as antidepressants is now restricted because of the severity of their side-effects. These include interactions with other drugs (e.g. ephedrine, phenylephrine) and with foods or drinks containing *tyramine (e.g. cheese or red wine) to produce a sudden and dangerous increase in blood pressure. *Moclobemide is a reversible inhibitor of monoamine oxidase A (RIMA), with less severe side-effects. See also selegiline.... mao inhibitor