Current approaches to therapy for depression are founded on observing a balance of the therapeutic activity of the drugs utilized and their safety. An increasing number of antidepressants with diverse pharmacological profiles of action are available. However, to maintain a positive therapeutic effect, TCAs have an affinity for numerous receptors, leading to the development of side effects. In order to prevent them, third-generation antidepressants affecting both serotoninergic and noradrenergic systems were created. They are not inferior to tricyclic antidepressants in effectiveness but do not lead to the development of widely known side effects. One representative of a new generation of antidepressants is duloxetine – a selective, potent, and balanced inhibitor that has proven effective in the fight against depression.
Duloxetine is an antidepressant, a substance of a new generation, which is often utilized for the treatment of depression due to its qualities. The drug weakly inhibits dopamine uptake and has no significant affinity for histamine, dopamine, choline, and adrenoreceptors (Osani & Bannuru, 2019). It has a central mechanism of pain syndrome suppression, primarily manifested by an increased pain sensitivity threshold in the neuropathic etiology of distress syndrome. The mechanism of therapeutic action of duloxetine in depression is due to the inhibition of serotonin and noradrenaline reuptake and, consequently, increased serotoninergic and noradrenergic neurotransmission in the CNS (Osani & Bannuru, 2019). Duloxetine normalizes the pain threshold and reduces the severity of aches in a chronic distress model. Its analgesic effect is caused by slowing down the transmission of nociceptive impulses in the CNS.
The drug is sufficiently absorbed after oral administration, and Cmax in plasma is reached several hours after administration. Simultaneous food intake slows down absorption, the period of getting Cmax in blood increases from 6 to 10 hours, and absorption declines (approximately by 11%) (Osani & Bannuru, 2019). It is extensively metabolized in the body, and the metabolites are excreted mainly in the urine. CYP 2D6 and CYP 1A2 isoenzymes catalyze the formation of the two primary metabolites of duloxetine (glucuronide coupled to 4-hydroxyduloxetine, sulfate connected to 5-hydroxy, methoxy-duloxetine) (Osani & Bannuru, 2019). The metabolites formed have no pharmacological activity. All these pharmacological properties make the drug effective and contribute to its impact on the neurological system.
Psychological Effects of Taking Duloxetine
Duloxetine is one of the most effective treatments for depression or other anxiety disorders. According to scientific hypotheses, depressive disorders are caused by a deficiency of noradrenaline or serotonin in specific brain structures (Lisinski et al., 2020). Mood-enhancing medications such as thymoleptics are used to treat these pathological conditions. Duloxetine is an antidepressant that inhibits the reuptake of mediators (serotonin and noradrenaline) at nerve cell intercellular contacts (synapses). As a result, the serotoninergic and noradrenergic transmission of impulses in the nervous system is enhanced.
Moreover, duloxetine has an analgesic effect, accelerating the treatment pace. It acts as the central mechanism of pain syndrome suppression, increases the threshold of pain sensitivity, and thus affects the patient’s well-being (Lisinski et al., 2020). After taking it, the patient gets the hormones needed, which directly affect one’s mood and activity level. Almost all individuals who have used the drug have experienced positive changes (Lisinski et al., 2020). It is the first sign of the effectiveness of Duloxetine, which will be discussed in detail below.
Effectiveness of Duloxetine
The antidepressant continues to be utilized more frequently in practice because of its high effectiveness. Numerous studies prove that the drug’s therapeutic effect is characterized by persistence and continuously increases against the background of another intake. Ninety percent of patients report a change in their mood, suicidal thoughts, lethargy, and psychopathological manifestations of anxiety (Lisinski et al., 2020). It is likewise vital to note that the drug is particularly effective after the first week of use. Pain reduction was observed in patients with and without a concurrent major depressive disorder. The higher amount was associated with more adverse reactions and premature treatment discontinuation. Analysis of drug dynamics revealed the presence of a steady decrease in the severity of anxiety throughout therapy, primarily due to mental and later somatic components (Lisinski et al., 2020). It proves the effectiveness of duloxetine prescription as a means to combat depression. However, like any medication, it has unintended effects that are important to consider when prescribing.
Unintended Effects of Duloxetine
Taking the drug may be accompanied by several side effects that should not be neglected. These include dizziness, headache, dry mouth, nausea, sleep disturbances, decreased appetite, blurred vision, decreased libido, increased blood pressure and blood glucose levels, and suicidal thoughts (Rodrigues-Amorim, 2020). It is essential to comprehend that if one of these symptoms is observed, it is crucial to immediately examine the patient and decide whether to continue or stop taking it. The body’s reaction to the substance can be quite different, with the appearance of suicidal thoughts being particularly dangerous and indicative of the wrong treatment option.
Moreover, it is essential to know that abruptly stopping duloxetine develops withdrawal syndrome. Stop taking duloxetine this way is harmful as it can cause specific symptoms such as dizziness, sensory disturbances, sleep disturbances, agitation or anxiety, nausea and vomiting, tremors, headaches, irritability, diarrhea, profuse sweating, and dizziness (Rodrigues-Amorim, 2020). Duloxetine blood tests are not mandatory when using the drug but are likewise important. It allows one to determine the therapeutically effective drug dose in each case and the degree of its interaction with other medications taken simultaneously.
The Alleged Effects of Duloxetine
By functioning simultaneously on both serotonin and norepinephrine deficiency, duloxetine can impact the entire spectrum of depressive symptoms. It affects anxiety and pain syndrome due to the serotonergic effect, cognitive impairment, lethargy, fatigue, and pain syndrome due to the noradrenergic and dopaminergic effects. It should be noted that, according to numerous studies, even at a dose of 60 mg/day, effectively and quickly (within a week) reduces the severity of both depressive syndrome and anxiety symptoms (including generalized anxiety disorder (Rodrigues-Amorim, 2020). At the same time, several studies demonstrate the superiority of this drug in efficacy and tolerability compared to SSRIs and some other groups of antidepressants.
Of particular importance is the effect of duloxetine on pain syndromes (whether associated with depression or not). The use of antidepressants in pain relief is caused by the proximity of the pathogenesis of depression and pain (Rodrigues-Amorim, 2020). In pain syndromes, there is insufficient antinociceptive innervation from the central nervous system, and accordingly, the pain impulse becomes significantly generalized. When prescribing a double-acting antidepressant and restoring mediator activity, the pain impulse is suppressed rather quickly. Moreover, it is crucial to consider the dosage at which the desired results are achieved. Comprehending the nature of the dosage and the effects of duloxetine will facilitate an individualized approach to the patient and, consequently, an effective treatment.
It can be concluded that during treatment with duloxetine, there is a reduction of psychopathological manifestations (depressive, anxious) diseases and a decline in pain sensations. Thus, the drug affects the spectrum of symptoms, including nervous and reflective components and mild and moderate depression. The rapid onset of the medicine’s therapeutic effects, noticeable to the patient, increases compliance and promotes restoring social functioning. Duloxetine is an effective and easily tolerated antidepressant providing rapid and positive treatment results.
Lisinski, A., Hieronymus, F., Näslund, J., Nilsson, S., & Eriksson, E. (2020). Item-based analysis of the effects of duloxetine in depression: A patient-level post hoc study. Neuropsychopharmacology, 45(3), 553-560.
Osani, M. C., & Bannuru, R. R. (2019). Efficacy and safety of duloxetine in osteoarthritis: A systematic review and meta-analysis. The Korean Journal of Internal Medicine, 34(5), 966.
Rodrigues-Amorim, D., Olivares, J. M., Spuch, C., & Rivera-Baltanás, T. (2020). A systematic review of efficacy, safety, and tolerability of duloxetine. Frontiers in Psychiatry, 11, 554899.