Central nervous system disorders mania

Neurochemical theories for the affective disorders propose that there is a link between dysfunctional monoaminergic synapses within the central nervous system (CNS) and mood problems. The original focus was the neurotransmitter noradrenaline, or NA (note noradrenaline is called norepinephrine, or NE, in American texts). Schildkraut (1965) suggested that depression was associated with an absolute or relative deficiency of NA, while mania was associated with a functional excess of NA. Subsequently, another monoamine neurotransmitter 5-hydroxytryptamine (5-HT), or serotonin, was put forward in a rival indoleamine theory (Chapter 2). However, it was soon recognised that both proposals could be reconciled with the available clinical biochemical and pharmacological evidence (Luchins, 1976 Green and Costain, 1979). 

Another problem facing the diagnosis of depression or mania is the fact that other medical conditions can cause similar symptoms. Among them are illnesses such as thyroid diseases, infectious diseases (the flu), cancers of the central nervous system, neurological disorders (multiple sclerosis), blood diseases, and even some reactions to metal toxicity. 

Lithium, whose proprietary names include Eskalith, Lithane, Lithonate, and others, is administered as lithium carbonate and used for treatment of the manic phase of affective disorders, mania, and manic-depressive illness. It is postulated to act by enhancing reuptake of catecholamines, thereby reducing their concentration in the neuronal junction. This produces a sedating effect on the central nervous system. Lithium also modulates the distribution of sodium, calcium, and magnesium in nerve cells, which reduces the rate of glucose metabolism that effects nerve function. The actual mechanism of action of lithium in affecting mania remains theoretical. 

Several medical, medication-induced, or substance-related causes of mania and depression have been identified (see Table 68-2 for causes of mania and Table 67-1 in Chap. 67 on depressive disorders for causes of depression). " A complete medical, psychiatric, and medication history physical examination and laboratory testing are necessary to rule out any organic causes of mania or depression. An accurate diagnosis is important because some psychiatric and neurologic disorders present with manic-like symptoms. For example, attention-deficit/hyperactivity disorder and a manic episode have similar characteristics thus individuals with bipolar disorder may be misdiagnosed and prescribed central nervous system stimulants. Use of any substance that affects the central nervous system (e.g., alcohol, antidepressants, caffeine, central nervous system stimulants, hallucinogens, or marijuana) can worsen symptoms and decrease the... 

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