Characteristics of fluvoxamine-induced nausea

Looking beyond 5-HT(3) receptors: a review of the wider role of serotonin in the pharmacology of nausea and vomiting

The concept that 5-hydroxytryptamine (5-HT; serotonin) is involved in the emetic reflex was revealed using drugs that interfere with its synthesis, storage, release and metabolism ahead of the discovery of selective tools to modulate specific subtypes of receptors. This review comprehensively examines the fundamental role of serotonin in emesis control and highlights data indicating association of 5-HT1-4 receptors in the emetic reflex, whilst leaving open the possibility that 5-HT5-7 receptors may also be involved. The fact that each receptor subtype may mediate both emetic and anti-emetic effects is discussed in detail for the first time. These discussions are made in light of known species differences in emesis control, which has sometimes affected the perception of the translational value of data in regard to the development of novel anti-emetic for use in man.

A case with occurring adverse effects when cross-over titration from fluvoxamine to paroxetine associated with increasing the plasma fluvoxamine level in major depressive disorder

Selective serotonin reuptake inhibitors (SSRIs) are first line drugs for treating not only depressive disorder but also anxiety disorder. Fluvoxamine, a SSRI, is mainly metabolized by cytochrome P450 (CYP) 2D6 and 1A2. However, paroxetine, an another SSRI is potent inhibitor for CYP 2D6. We report a case with depression whose plasma fluvoxamine level rapidly increased after the addition of paroxetine while switching from fluvoxamine to paroxetine. The case indicates that emerging adverse effects via the pharmacokinetic interaction of these drugs when switching patients from fluvoxamine to paroxetine can occur.

Role of selective serotonin reuptake inhibitors in psychiatric disorders: a comprehensive review

The selective serotonin reuptake inhibitors (SSRIs) have emerged as a major therapeutic advance in psychopharmacology. As a result, the discovery of these agents marks a milestone in neuropsychopharmacology and rational drug design, and has launched a new era in psychotropic drug development. Prior to the SSRIs, all psychotropic medications were the result of chance observation. In an attempt to develop a SSRI, researchers discovered a number of nontricyclic agents with amine-uptake inhibitory properties, acting on both noradrenergic and serotonergic neurons with considerable differences in potency. A given drug may affect one or more sites over its clinically relevant dosing range and may produce multiple and different clinical effects. The enhanced safety profile includes a reduced likelihood of pharmacodynamically mediated adverse drug-drug interactions by avoiding affects on sites that are not essential to the intended outcome. SSRIs were developed for inhibition of the neuronal uptake pump for serotonin (5-HT), a property shared with the TCAs, but without affecting the other various neuroreceptors or fast sodium channels. The therapeutic mechanism of action of SSRIs involves alteration in the 5-HT system. The plethora of biological substrates, receptors and pathways for 5-HT are candidates to mediate not only the therapeutic actions of SSRIs, but also their side effects. A hypothesis to explain these immediate side effects is that 5-HT is increased at specific 5-HT receptor subtypes in discrete regions of the body where the relevant physiologic processes are regulated. Marked differences exist between the SSRIs with regard to effects on specific cytochrome P450 (CYP) enzymes, and thus the likelihood of clinically important pharmacokinetic drug-drug interactions. Although no clear relationship exists between the clinical efficacy, plasma concentration of SSRIs, nor any threshold that defines toxic concentrations, but therapeutic drug monitoring (TDM) may be useful in special populations, such as in elderly patients, poor metabolizers (PM) of sparteine (CYP2D6) or mephenytoin (CYP2C19), and patients with liver and kidney impairment. Several meta-analyses have reviewed the comparative efficacy of TCAs and SSRIs, and concluded that both TCAs and SSRIs have similar efficacy in the treatment of depression. SSRIs have demonstrated better efficacy and tolerability in the treatment of obsessive compulsive disorder (OCD). They have also been found to be effective in the treatment for social anxiety disorder both in reducing total levels of social anxiety and in improving overall clinical condition. The benefit of SSRIs in anorexia nervosa (AN) is apparently short-term unless medication is given in the context of nutritional or behavioral therapy. No single antidepressant can ever be recommended for every patient, but in a vast majority of patients, SSRIs should be considered as one of the first-line drugs in the treatment of depression.