Fluvoxamine is an antidepressant that belongs to the group of selective serotonin reuptake inhibitors. In Germany, the active ingredient has been approved for the treatment of depression and obsessive-compulsive disorder, but it is also frequently used to treat anxiety and panic disorders and post-traumatic stress disorder. When using the drug, interactions with other medications such as monoamine oxidase (MAO) inhibitors must be considered, and significant side effects may occur.
What is fluvoxamine?
The active ingredient is used to treat depression and obsessive-compulsive disorder. Fluvoxamine is a drug with the chemical formula C15H21F3N2O2. It contains a monocyclic aromatic ring and has been approved as an antidepressant in Germany since the mid-1980s. The drug belongs to the group of selective serotonin reuptake inhibitors (SSRIs). The abbreviation SSRI is derived from the English term “selective serotonin reuptake inhibitor”. The monocyclic structure and its special binding ability and affinity to σ-receptors (sigma-receptors) distinguish fluvoxamine from most other antidepressants, which have a special binding affinity to opioid receptors. Among other things, the drug shows a strong interaction with reversible and irreversible MAO inhibitors (monoamine oxidase inhibitors), which non-selectively inhibit the breakdown of neurotransmitters such as serotonin, norepinephrine, and dopamine and are also used as antidepressants. Fluvoxamine must therefore not be taken together with MAO inhibitors. Established withdrawal periods must be observed before switching therapy from MAO inhibitors to fluvoxamine or vice versa.
Pharmacologic Effects
As a selective serotonin reuptake inhibitor, fluvoxamine exclusively affects the reuptake or reverse transport of serotonin into the vesicles of certain cells or the breakdown of this neurotransmitter, increasing its concentration in the synaptic cleft. Due to the selective mode of action of the drug, degradation or reverse transport of the other neurotransmitters from the group of monoamines, such as epinephrine, dopamine, melatonin and others, are not affected. Fluvoxamine therefore leads to a unilateral increase in the concentration of serotonin in the synaptic cleft due to its longer residence time there. Psychological effects are attributed to the monoamine serotonin as a neurotransmitter in the central nervous system (CNS). Among other things, serotonin is considered to have mood-lifting, motivating and anxiety-relieving effects. A deficiency of serotonin can often be detected in depressive moods and depression. On the assumption that remedying the reduced serotonin concentration will also resolve the depressive mood, attempts are made to remedy the relative deficiency by supplying additional serotonin or by preventing rapid inactivation of the neurotransmitter. Taking fluvoxamine results in increased serotonin concentration via inhibition of rapid inactivation of serotonin. If the serotonin concentration exceeds a certain level, the effect of the neurotransmitter may be nearly reversed. A serotonin syndrome sets in, typically characterized by symptoms such as anxiety, inner restlessness, muscle tension, tremors and muscle twitching. Serotonin syndrome may develop, for example, if the interaction of fluvoxamine with MAO inhibitors is not observed and uncontrollably high serotonin levels develop.
Medical application and use
The use of fluvoxamine, in its capacity as a selective serotonin reuptake inhibitor, results in a rising serotonin level in the blood and is therefore considered for the treatment of all mental disorders associated with a lowered serotonin level. This applies primarily to pathological depression. It is not yet sufficiently known whether manifest depression is the cause or consequence of serotonin deficiency. Fluvoxamine is therefore prescribed primarily for the treatment of depression. According to its original approval in the mid-1980s, the drug is also explicitly intended to improve obsessive-compulsive disorder. In the course of further applications, which clearly go beyond the originally researched disease spectrum, the drug is also frequently used for the therapy of anxiety disorders, panic attacks, post-traumatic stress disorders and for social phobia, as well as for irritable bowel syndrome.Treatment with the SSRI fluvoxamine is also quite common in diagnosed borderline syndrome, which can be classified in the border region between neurosis and manifest psychosis. Empirical evidence has emerged that anxiety disorders, which can develop into social phobia, for example, are also accompanied by lowered serotonin levels. In order to treat the social phobia itself and thus to prevent the development of a number of negative concomitant symptoms, the use of fluvoxamine is considered and also sometimes preferred by many physicians. In addition to its efficacy, the drug is often valued for its relatively short physiological half-life of about 15 hours. The short half-life permits a rapid switch to an alternative psychotropic drug within a few days if intolerance to the drug is detected.
Risks and side effects
Fluvoxamine, like other inhibitors of selective serotonin inhibitors, interferes relatively insensitively, unilaterally, and systemically with the metabolism of monoamines. There is a unilateral increase in serotonin concentration in the nervous system without a full understanding of the associated systemic effects on many relevant metabolic processes. Despite the undoubted treatment success in improving a number of psychopathological disorders, the use of fluvoxamine is often accompanied by emerging adverse side effects. For example, anxiety, drowsiness, tremors, and sleep disturbances may occur after taking fluvoxamine. Likewise, there is often an increase in heart rate as well as sweating and hypersensitivity reactions of the skin. Particularly in combination with drugs that lead to an increase in serotonin levels by other means, serotonin syndrome can develop, a toxic oversupply of serotonin. Serotonin syndrome is typically accompanied by clouding of consciousness, muscle rigidity, tremors, and fever and requires immediate medical attention.
