Fluvoxamine belongs to the selective serotonin reuptake inhibitors (SSRI). By inhibition of serotonin reuptake, fluvoxamine binds to 5-HT1 receptors in neuronal membranes, increases serotonin concentration and leads to an antidepressant effect.
Fluvoxamine has a very low affinity for adrenergic receptors as well as for dopaminergic, histamine and muscarinic receptors, and does not exhibit clinically significant effects arising from binding to these receptors.
It is used to treat major depressive episodes as well as obsessive-compulsive disorders.
Pharmacokinetics
Fluvoxamine is subject to first-pass metabolism in the liver, and its average bioavailability is 53%. The main metabolism pathway is via the liver, specifically via the CYP2D6 enzyme. Studies have shown that fluvoxamine is a potent inhibitor of CYP1A2 and CYP2C19 enzymes and a moderate inhibitor of CYP3A4 and CYP2D6. These enzymes are important because many drugs are metabolized via these enzymes, which mean that fluvoxamine can interact with these drugs.
Taking food does not affect the absorption rate of the active substance, and fluvoxamine tablets can be taken regardless of the meal.
After passing through the liver, fluvoxamine is converted to nine metabolites that are excreted by the kidneys.
Since it is metabolized through the liver and excreted by the kidneys, fluvoxamine must be used with caution in patients who have impaired liver or kidney function. In these patients, it is recommended to decrease the dose.
Warnings and precautions
fluvoxamine is contraindicated in patients who are taking or have recently taken (in the past 14 days) drugs that are called MAO inhibitors (such as: moclobemide, isocarboxazide, tranylcypromine, selegiline, linezolid, and others). Concomitant use with these medicines can lead to the serotonin syndrome - a very serious condition that can endanger the patient's life.
According to the FDA, concomitant use with the following drugs is also contraindicated:
•Pimozide - a medicine used to treat psychiatric disorders. Fluvoxamine increases the concentration of pimozide in the blood which increases the risk of side effects, such as arrhythmia, which can endanger life!
•Alosetron - a serotonin antagonist used to treat symptoms of irritable bowel syndrome. Fluvoxamine increases the concentration of alosetron in the blood, which increases the risk of side effects.
•Tizanidine - a muscle relaxant used to treat muscle spasms. Simultaneous administration with this medicine increases the risk of side effects such as drowsiness, low blood pressure, confusion, and slurred speech.
•Thioridazine - a medicine used to treat schizophrenia. Simultaneous administration with this medicine increases the risk of cardiac arrhythmia, which may be potentially life-threatening!
Patients taking fluvoxamine tablets may experience suicidal ideation. If you are experiencing suicidal thoughts, contact your doctor immediately. Sometimes, symptoms of depression may exacerbate during fluvoxamine therapy (panic attack, agitation, aggression, anxiety, mania and insomnia). If your depression symptoms worsen, contact your doctor immediately.
Careful monitoring of patients at the beginning of therapy is recommended and also whenever the dose of the drug is changed.
The use of fluvoxamine should gradually be discontinued, as abrupt discontinuation may cause withdrawal syndrome and symptoms such as: dizziness, agitation, irritability, dysphoria, emotional liability, headache, lethargy, and insomnia.
Use of fluvoxamine during pregnancy and breastfeeding
Studies have shown that the use of selective serotonin uptake inhibitors in the last trimester increases the risk of persistent pulmonary hypertension - this adverse effect occurs in 0.5% of pregnant women taking SSRIs compared to 0.1-0.2% of pregnant women in a control group.
Studies in rats have shown that the use of 120mg / kg can lead to fetal eye development defects and to an increase in the risk of fetal death.
Fluvoxamine should be used during pregnancy only if the benefit to the mother outweighs the risk to the fetus.
This medicine is secreted into breast milk and can lead to potentially serious adverse effects. For this reason, breastfeeding should be discontinued while taking fluvoxamine
Dosage instructions
The recommended starting dose in the treatment of depression and obsessive-compulsive disorders in adult patients is 50mg once daily, before bedtime. The dose should be gradually increased (on a weekly basis) until the desired effect is achieved.
The maximum dose is 300mg daily.
Depression therapy usually lasts at least 6 months. Improvement of symptoms is expected 3-4 weeks after initiation of therapy.
Fluvoxamine is not approved for the treatment of depression in patients under the age of 18. The usual starting dose in the treatment of obsessive-compulsive disorders in children aged 8-17 years is 25mg once daily, before bedtime. The dose may be gradually increased until the desired effect is achieved. The maximum daily dose for children aged 8-17 years is 200mg.
Fluvoxamine is not approved for the treatment of obsessive-compulsive disorders in children under the age of 8

Interactions
Fluvoxamine should not be used concurrently with the following medicines:
•MAO inhibitors such as: Moclobemide, Isocarboxazid,Tranylcypromine, (used to treat
•depression). Selgeline, rasagline, (used to treat parkinson’s diseaes) Linezolide (antibiotic) and others. Simultaneous administration increases the risk of serotonin syndrome.
•5-hydroxytryptophan - a medicine used to treat depression. Simultaneous administration increases the risk of serotonin syndrome.
•Dextromethorphan - antitussive agent. Simultaneous administration increases the risk of serotonin syndrome.
•Ramelteon - a medicine used to treat insomnia. Simultaneous administration significantly increases the concentration of ramelteon in the blood, thereby increasing the risk of its side effects.
•Ranolazine - a medicine used to treat angina. Simultaneous administration significantly increases blood concentrations of ranolazine, which increases the risk of arrhythmias.
•Phenylpropanolamine - a medicine used to treat nasal congestion. Simultaneous administration increases the risk of side effects of phenylpropanolamine, such as nervousness and anxiety.
•Aminophylline and theophylline - drugs used for asthma treatment.
•Bupropion-a medicine used to support smoking cessation treatment as well as for depression treatment. Simultaneous administration increases the risk of seizures.
•Narcotic analgesics such as fentanyl, pentazocine, tramadol, alfentanil, and others.
•Buspirone - anxiolytic. Simultaneous administration increases the risk of serotonin syndrome.
•Cisapride - a medicine used to treat gastrointestinal disorders. Fluvoxamine increases the concentration of cisapride in the blood, thereby increasing the risk of arrhythmias.
•Cilostazol - a medicine used to treat intermittent claudication. Simultaneous administration increases the risk of side effects of cilostazole.
•Immunosuppressants, such as Everolimus, Fluvoxamine significantly increases the concentration of this drug in the blood, which increases the risk of side effects such as pneumonia and bleeding.
•Benzodiazepines: such as bromazepam, alprazolam, lorazepam, and others
•Warfarin- anticoagulant medicine.
Tell your doctor about all the medicines you are taking.
Adverse effects
Fluvoxamine may cause the following adverse effects:
•Digestive disorders (nausea, vomiting, diarrhea, dyspepsia, flatulence, constipation, gum inflammation, and others).
•Dilation of blood vessels.
•High blood pressure.
•Palpitations.
•Tachycardia.
•Insomnia.
•Hallucinations.
•Convulsions.
•Agitation.
•Decreased libido.
•Hematospermia.
•Menorrhagia.
•Dry mouth.
•Dizziness.
•Upper respiratory tract infections.
•Increased sweating.
•Urinary tract infections.
•Changes in behavior or mood.
•Nosebleeds.
•Weakness.
•Sore throat.
•Galactorrhea.
•Hyperprolactinaemia.
•Inappropriate secretion of antidiuretic hormone.
•Agranulocytosis.
•Pain in the joints and muscles.

Tell your doctor if you notice any side effects.