Fluoxetine is an antidepressant, one of the main representatives of the group of selective serotonin reuptake inhibitors. His antidepressant effect is combined with a stimulating one. It improves mood, reduces tension, anxiety and fear, eliminates dysphoria. Does not cause orthostatic hypotension, sedation, is not cardiotoxic. It has anorexigenic property.
Fluoxetine is preferable for depressions that occur with motor inhibition and hypersomnia, it can be poorly tolerated by patients with psychomotor agitation, anxiety and insomnia - this kind of symptoms can worsen.
Fluoxetine was first registered in 1974 by scientists at the Eli Lilly and Company. He was presented to the Food and Drug Administration of the United States in February 1977. Eli Lilly received final approval for the sale of the drug in December 1987. Fluoxetine was released from patent protection in August 2001.
By 2011, despite the fact that many antidepressants appeared on the pharmacological market, fluoxetine was a leader. Thus, in the United States in 2010, over 24.4 million prescriptions for fluoxetine were written out, making it the third most popular prescription antidepressant after sertraline and citalopram. In 2011, 6 million prescriptions for fluoxetine were written in the UK.
Cases of suicide and other types of aggressive behavior have become widely known in the United States against the background of fluoxetine intake, as well as publications in the media and lawsuits against the pharmaceutical company Eli Lilly and Company about this. In total, 70 lawsuits were filed against Eli Lilly. In all cases, it was argued that prior to taking this drug, patients did not experience suicide. The company's internal documents show that for a long time Eli Lilly concealed information about suicides due to the use of Prozac in clinical trials and explained them to overdose or depression. As it turned out, the company has known since 1978 that fluoxetine can cause a strange excited state in some patients, provoking them to suicide or murder. In particular, Eli Lilly excluded 76 of the 97 cases of suicide in persons taking Prozac from a post-marketing observational study, the results of which were provided to the FDA.
By 1999, the FDA had received reports of more than 2,000 suicides related to fluoxetine, and a quarter of the messages clearly indicated the development of agitation and akathisia in patients, which also cause an increased risk of suicide. In 2006, EMA (European Medical Agency) announced that parents and doctors should closely monitor children and adolescents receiving fluoxetine treatment, especially for their suicidal tendencies.
By 2000, the amount of compensation in connection with Prozac, which Eli Lilly had to pay, reached $ 50 million. Lawsuits were also filed in connection with the side effects of Symbiax, a combination drug containing olanzapine and fluoxetine. According to reports of some patients taking Symbiax during pregnancy, the drug can cause such birth defects as cleft lip and palate, spina bifida, anencephaly, and clubfoot.
The book by the famous American psychologist Irving Kirsch, The Emperor's New Drugs: Disrupting the Myth of Antidepressants, describes the results of a review of 42 clinical trials of 6 antidepressants, including 4 antidepressants of the SSRI group - fluoxetine, paroxetine, sertraline and citalopram. The data of some of these studies have not been published before, they were silent about the results. After analyzing the research, Kirsch noted that the difference between drugs and placebo averaged only 1.8 points on the Hamilton scale - a difference, although statistically significant, but clinically meaningless. According to another study conducted by Kirsch and co-authors (a meta-analysis of 35 clinical trials of 4 antidepressants, including fluoxetine), the difference between antidepressants and placebo reached clinical significance only in very severe depression. The results of the Kirsch study caused a wide resonance and were discussed both in scientific journals and in popular media.
Peter Goetsche, one of the founders of Cochrane, a professor of design and analysis of clinical research at the University of Copenhagen, the author of over 70 articles in leading medical journals, calls fluoxetine a “creepy medicine” and reports that the top management of Eli Lilly in the late 1980s initially wanted to postpone its release and only the fact that the company was in a deep financial crisis at that time led to the release of the drug on the market. According to Goetche, the German drug regulator, based on the results of fluoxetine evaluation, concluded: “Comparing the benefits and risks, we came to the conclusion that the drug is completely unsuitable for the treatment of depression”. In order to achieve approval of the drug in Sweden (which should have a positive effect on the FDA's decision regarding Prozac), doctors were first invited to a Caribbean resort for a week and then paid a bribe of $ 20,000. At the same time, from the data of clinical trials cited in the registration application, the references to lethal side effects disappeared, and the original wording “Five subjects had hallucinations and tried to commit suicide, which the four managed to do” was changed to “Other five subjects there were different effects”.
In addition, Eli Lilly bribed members of an FDA advisory group that was convened in 1991 to review fluoxetine data. The advisory group concluded that fluoxetine is safe, despite the questions raised by safety expert David Graham and several others.
As Peter Goetshe points out, Eli Lilly illegally promoted fluoxetine with some unapproved indications, such as shyness, eating disorders, and low self-esteem. Fluoxetine-induced trials in the pharmaceutical industry-sponsored trials: in direct comparative trials, where Prozac was the main subject of the study, a significantly larger number of patients became better from him than in trials in which Prozac was a comparator (used to compare).
Manifestations of fluoxetine interactions with other drugs can be observed not only during its reception, but also within 2-3 weeks after its cancellation.
Enhances the effects of diazepam, ethanol and hypoglycemic drugs, tricyclic antidepressants, trazodone, alprazolam, triazolam, beta-blockers, carbamazepine, sodium valproate, phenytoin, barbiturates. Reduces the anti-anxiety effect of buspirone. It is not recommended to combine with trazodone, alprazolam, buspiron, lithium, bupropion. Changes the concentration of lithium in the blood, which increases the risk of neurotoxicity. Fluoxetine causes an increase in the level of the main metabolite of bupropion - hydrox-bupropion, which can lead to clinical manifestations of the toxic effect of this metabolite: catatonia, confusion and arousal.
When fluoxetine is combined with tricyclic antidepressants, the effect of cardiotoxicity increases dramatically as the concentration of tricyclic antidepressants in the blood rises. It is not recommended to combine with imipramine, desipramine, nortriptilin. Studies have shown that a stable concentration of imipramine and desipramine in the blood after the addition of fluoxetine increases 2-10 times. Even after discontinuing fluoxetine, this effect may appear within 3 weeks, since fluoxetine has a long half-life.
The simultaneous use of fluoxetine and typical neuroleptics leads to an increased risk of extrapyramidal symptoms and to its strengthening. It is not recommended to combine fluoxetine with haloperidol. When combined with drugs that have a depressant effect on the central nervous system, the inhibitory effect on the central nervous system of both drugs is enhanced.
Fluoxetine can increase the severity of psychomotor disorders, if it is used in conjunction with benzodiazepine tranquilizers.
Macrolide antibiotics (erythromycin, clarithromycin, etc.) increase the concentration of fluoxetine in the blood with the possible development of toxic effects ; clarithromycin in combination with fluoxetine can cause psychosis . Tryptophan increases the serotonergic properties of fluoxetine, so an increased intake of tryptophan, including with food, can cause increased agitation, anxiety, and gastrointestinal disturbances.
Fluoxetine in combination with statins can cause manifestations of myositis.
Taking fluoxetine with mirtazapine, according to a study in 2009, in which 105 patients participated, allows you to increase the number of patients who have achieved a long-term, sustained remission by 2 times compared with therapy with a single drug. Such combinations are used for resistant (resistant to treatment) depression. Fluoxetine can also be used with bupropion for this purpose, since they do not belong to the same group of antidepressants.
Antidepressants - MAO inhibitors should not be used in conjunction with fluoxetine because of the possible development of serotonin syndrome. Fluoxetine treatment can begin no less than 14 days after discontinuation of irreversible MAO inhibitors. Between the end of treatment with fluoxetine and the start of treatment with irreversible MAO inhibitors should be maintained for at least 5 weeks, in elderly patients - at least 8 weeks. An interval of at least 2 weeks is required between the end of taking fluoxetine and the start of taking other SSRIs.
Serotonin's Syndrome analgesics, carbamazepine, lithium preparations, metoclopramide.
When fluoxetine was used together with calcium channel blockers (verapamil, nifedipine), headaches, swelling, nausea were observed. When combined with diuretics may develop hyponatremia.
With the simultaneous use of drugs with a high degree of protein binding, it is possible to increase the plasma concentration of free (unbound) drugs and increase the risk of adverse effects. Thus, with the combined use of fluoxetine and antithrombotic agents, fluoxetine and glycosides of digitalis, confusion, agitation, convulsions, and hypertension may develop.
Use with caution
Suicidal risk: with depressions, there is a likelihood of suicidal attempts that may persist until the onset of persistent remission. Separate cases of suicidal thoughts and suicidal behavior were described against the background of therapy with fluoxetine or shortly after its completion, similar to the action of other drugs of similar pharmacological action (antidepressants).
Careful observation of patients at risk is needed. Doctors should convince patients to immediately report any thoughts or feelings that are disturbing. Despite the fact that the effect of fluoxetine on the occurrence of such cases has not been established, data from joint studies on the use of antidepressants for mental disorders revealed an increased risk of suicidal thoughts and / or suicidal behavior in younger patients (under 25 years of age) compared with placebo.
Drug therapy of patients with high risk should be accompanied by monitoring by the attending physician. Physicians should encourage patients of different ages to report any unpleasant thoughts and feelings that arise at any time during therapy. In the course of studies in adult patients with major depressive disorder in both groups taking placebo and fluoxetine, the following risk factors for suicide were identified.
- more pronounced severity of depression
- the presence of thoughts about death
- weighting depression
- the development of insomnia
In the course of treatment with fluoxetine, a risk factor has also been the development of severe psychomotor agitation (for example, agitation, akathisia, panic). The presence or the occurrence of these conditions before or during therapy is a reason to strengthen the clinical control or to correct the treatment being conducted.
Skin rash: skin rash, anaphylactic reactions and progressive systemic disorders, sometimes serious with involvement of the skin, kidneys, liver and lungs in patients taking fluoxetine, have been reported. If skin rash or other possible allergic reactions appear, the etiology of which cannot be determined, fluoxetine should be discontinued.
Epileptic seizures: as with other antidepressants, fluoxetine should be used with caution in patients who have previously had epileptic seizures.
Hyponatremia: there have been cases of hyponatremia (in some cases, the serum sodium concentration was less than 110 mmol / l). In general, similar cases were observed in elderly patients and in patients who received diuretics due to a decrease in circulating blood volume.
Glycemic control: hypoglycemia was observed in patients with diabetes mellitus during fluoxetine treatment, and after discontinuation of the drug hyperglycemia developed. At the beginning or after the end of treatment with fluoxetine, it may be necessary to adjust the doses of insulin and / or hypoglycemic drugs for oral administration.
Liver / kidney failure: Fluoxetine is extensively metabolized in the liver and excreted by the kidneys. Patients with severely impaired liver function are advised to prescribe lower doses of fluoxetine, or prescribe the drug every other day. When fluoxetine was taken in a dose of 20 mg / day for two months by patients with severe impaired renal function (CC <10 ml / min) in need of hemodialysis, there was no difference in fluoxetine and norfluoxetine plasma levels from healthy individuals with normal function the kidneys.
Use during pregnancy and breastfeeding
Pregnancy: 2072 cases of pregnancy occurring while receiving fluoxetine in the first trimester are known. Available data indicate the absence of undesirable effects on the course of pregnancy or on the development of the fetus or newborn. However, caution should be exercised, especially in late pregnancy, as there are rare reports of the development of withdrawal syndrome in the newborn (short-term restlessness, difficulty in feeding, rapid breathing and irritability) if the mother took the drug shortly before delivery. Fluoxetine can be used during pregnancy, provided that the intended benefit outweighs the potential risk.
Breastfeeding: Fluoxetine is excreted in breast milk, therefore, caution should be exercised in the appointment of fluoxetine to nursing mothers.
Childbirth: the effect of fluoxetine on the process of childbirth in humans is not known.