Depression monoamine therapy

Patients receiving monoamine oxidase inhibitors (MAOI) as antidepressant therapy have been especially subject to the hypertensive effects of vasoactive amines (52). These dietary amines have also been impHcated as causative agents ia migraine. Other aaturaHy occurring alkaloids (qv) have been recognized for centuries as possessing neurological stimulant and depressant properties. 

Recently research has focused on the action of lithium on serotonergic function. Lithium has been shown to facilitate the uptake and synthesis of 5-HT, to enhance its release and to increase the transport of tryptophan into the nerve terminal, an effect which probably contributes to the increased 5-HT synthesis. The net effect of these changes is to produce postsynaptic receptor events, which might explain why lithium, in combination with tryptophan and a monoamine oxidase inhibitor or a 5-HT uptake inhibitor, is often effective in therapy-resistant depression. 

Maintenance/Continuation/Extended treatment There is no evidence to indicate how long the depressed patient should be treated with nefazodone. However, it is generally agreed that pharmacologic treatment for acute episodes of depression should continue for at least 6 months. Whether the dose of antidepressant needed to induce remission is identical to the dose needed to maintain euthymia is unknown. In clinical trials, more than 250 patients were treated for at least 1 year. Switching to or from a monoamine oxidase inhibitor (MAOi) At least 14 days should elapse between discontinuation of an MAOI and initiation of therapy with nefazodone. In addition, wait at least 7 days after stopping nefazodone before starting an MAOI. 

The pharmacological inhibition of the serotonin eliminating enzyme MAO is used in the therapy of depression and hypertension. Tranylcypromine is an irreversible unselective MAO inhibitor which displays numerous interactions with amine-containing food and monoamine-related drugs, resulting in evenmally fatal hypertensive crisis, cranial hemorrhage, arrhythmias and seizure can occur. The coadministration with speciflc serotonin reuptake inhibitors (SSRI) can result in similar effects and is therefore contraindicated. Moclobemide, on the other hand, is a reversible inhibitor of MAOa, one of the two enzyme subtyppes (MAOa, MAOb) which is void of most interactions see with tranylcypromine. 

To date, only one antidepressant, amoxapine, has proven effective in the treatment of PMD as the sole therapy. Amoxapine is a chemical congener of the antipsychotic drug loxapine, so it possesses both dopamine-blocking and monoamine-enhancing properties. One double-blind study has confirmed that amoxapine appears to be as effective as the combination of a TCA and an antipsychotic. R. F. Anton and Burch [1990] randomly selected 46 inpatients with psychotic depression to either amoxapine [to 400 mg/day] or ami-... 

ECT is superior in efficacy when compared with placebo, sham ECT, and active drug therapy. Upon the introduction of effective pharmacotherapy for severe depression, the relative efficacy of drug versus ECT was frequently studied. Our review of the relevant literature led to an extrapolation of the data from selected studies (primarily class I or II designs) for a quantitative analysis of the efficacy of ECT versus other treatments for an acute depressive episode ( 53). The comparisons with ECT included simulated (or sham) ECT, placebo, the standard tricyclic antidepressants, and the monoamine oxidase inhibitors [ Table 8-1 (54, 55, 56, 57, 58 and 59), Table 8 2 (0g 6i 62 and 63), Table 8-3 (56, 61, 62, 63, 64, 65 and 66), and Table 8-4 (55, 60, 61, 62 and 63)]. We also compared the relative efficacy of the bilateral versus the UNID forms of administration [Table 8-5 (42, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77 and 78)]. A meta-analysis was... 

So the worst kind of sleep for depressives is the kind they get a lot of REM. That could be why REM deprivation temporarily lifts depression. And that could be why the antidepressants, especially the monoamine oxidase inhibitors (or MAOIs), work so well. They squash the overactive cholinergic system. REM deprivation does it for a day or two MAOIs do it for as long as the drug is on board. Isn t that interesting All of the reciprocities on the pathogenesis side of depression are mirrored on the therapeutic side. Let s fold the sleep and therapy facts into the integrated formula. 

From the existing literature, St. John s wort appears to be a safe and effective alternative in the treatment of depression. Tricyclic antidepressants and monoamine oxidase inhibitors can produce serious cardiac side effects, such as tachycardia and postural hypotension, and many unwanted anticholinergic side effects, including dry mouth and constipation. St. John s wort has proved to be free of any cardiac, as well as anticholinergic, side effects normally seen with antidepressant medications. Based upon limited studies, St. John s wort appears to be an acceptable alternative to traditional antidepressant therapy. 

Because suicide is one of the leading causes of death in elderly people and in other populations, rapid and effective treatment of depression is warranted. Current therapies include the use of electroconvulsive (shock) therapy, psychiatric intervention, and antidepressant drugs such as tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOIs), and serotonin-selective reuptake inhibitors (SSRIs). Recently, in the U.S., the use of St. John s wort (Hypericum perforatum) has become more prevalent, especially in the treatment of depression. 

Drugs and chemicals are known to cause activated interaction. The depressant action of opioid drugs is enhanced by drugs acting on the central nervous system (CNS) such as alcohol, anesthetics, anxiolytics, hypnotics, tricyclic antidepressants, and antipsychotics. Concomitant administration of opioid analgesics and monoamine oxidase inhibitors (MAOIs) should be avoided, or extra care should be taken if such a therapy is inevitable. Fatal reactions are reported when treated along with selegiline. Interactions also are reported with cyclizine, cimetidine, mexiletine, cisapride, metoclopramide, or domperidone. 

Iproniazid 24, an alkyl analog of the antituberculous drug isoniazid 25 (Figure 2.8), surprisingly showed mood-improving activity in several depressed tuberculosis patients, which turned out to result from a monoamine oxidase (MAO) inhibitory activity. Since the compound was already registered as an antituberculosis drug and since it constituted the very first effective treatment of depression, more than 400 000 patients received it within only one year after the first announcement of its antidepressant activity [2, 33], Later it was withdrawn from therapy, due to hepatotoxic side effects. 

While the monoamine hypothesis of depression is conceptually straightforward, it is in reality it is an oversimplification of a complicated picture. Other systems that are implicated in the aetiology of depression (and which provide potential targets for drug therapy) include the hypothalamopituitary-thyroid axis and the hypothalamopituitary-adrenal axis (HEA). The finding that 50% of depressed patients have elevated plasma cortisol concentrations constitutes evidence that depression may be associated with increased HPA drive. 

It may sometimes be better to give the drugs orally rather than up the nose. They interact with antihypertensives and can be a cause of unexplained failure of therapy unless enquiry into patient self-medication is made. Fatal hypertensive crises have occurred when patients treated for depression with a monoamine oxidase inhibitor have taken these preparations. 

Because of undesirable side effects associated with monoamine oxidase inhibitor therapy (see section 2.3.2), pharmaceutical companies nearly abandoned research on new analogs in the 1960s. The early MAO inhibitors were nonselective and irreversible. Today, efforts toward the development of monoamine oxidase inhibitors are focused on selective MAQA or MAOB inhibitors. Selective MAOB inhibitors are being examined in the treatment of, for example, schizophrenia, Alzheimer s disease, and Parkinson s disease. MAO-B inhibitors might be effective in the treatment of depression, but relatively little woik has been done in this area. Selegiline... 

Youdim MB (1980) Monoamine oxidase inhibitors as anti-depressant drugs and as adjunct to L-dopa therapy of Parkinson s disease. J Neural Transm Suppl 16 157-161... 

Studies have shown that individuals who smoke heavily are at high risk of depressive illness, either first onset or recurrent, if they cease smoking, especially without nicotine replacement therapy (Glassman et al., 1990). Although direct antidepressive effects of nicotine remain to be demonstrated, there is no question that nicotine can have significant salutary effects on mood, at least in deprived smokers (Foulds et al., 1997). As nicotine has significant effects on the release of monoamine neurotransmitters... 

The early pioneering work by Zeller et al. (115) on the potent MAO inhibitory effect of iproniazid—a structural modification of the tuberculostat Isoniazid—and his realization of the physiologic consequences that might arise from such a profound alteration in catecholamine metabolism, the actual confirmation by Brodie, Pletscher, and Shore (27) of the rise in brain monoamine levels following the administration of iproniazid and JB-516 (a-methylphen-ethylhydrazine), and the early euphoric effects noted by Selikoff, Robitzek, and Omstein (96) in tuberculosis patients on iproniazid therapy led Kline and his associates (67) to investigate the possible application of iproniazid in the treatment of mental depression. It was their conclusion that MAO inhibition and antidepressant effect had a causal relationship and that a new approach for the treatment of mental depression had been uncovered. The subject of the MAO inhibitors has been reviewed extensively up to 1960 by Pletscher, Gey, and Zeller (84) and by Biel, Horita, and Drukker (21) to 1963, in comprehensive reviews of the chemistry, biochemistry, pharmacology, clinical application, and structure-activity relationships of the MAO inhibitors. 

Even after years of research, it is still not clear which receptor sites or which monoamines are involved, although noradrenaline, serotonin and dopamine are all implicated. Neither does the theory explain how mania and depression can exist in the same patient. Much research has involved investigation of cerebrospinal fluid, blood and urine of patients to see if there are any abnormalities of monoamine metabolites. Although results may be complicated by diet, non-brain amines and the inevitable dmg therapy, evidence indicates that bipolar depression is associated with a decrease in dopamine activity, mania with an increase in dopamine activity [or depletion of inhibitory gamma-amino butyric acid (GABA)] and unipolar depression with a decrease in noradrenaline or serotonin activity or both. Levodopa (a precursor of dopamine) has been shown to produce symptoms of mania in patients with bipolar depression but not in those with unipolar depression. This still does not explain the swings in mood and little is known about how or why alternation between depression and mania occurs. 

Trimipramine is contraindicated in patients with known hypersensitivity to tricyclic antidepressants, trazodone, and related compounds in the acute recovery phase of myocardial infarction (MI), because the drug depresses cardiac function and causes dysrhythmia in patients in coma or severe respiratory depression (additive CNS and respiratory depression) and during or within 14 days of therapy with monoamine oxidase inhibitors. 

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