Microplastics and Misinformation: What Science Really Says
November 12, 2025
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Brand Name :
Effexor, Effexor XR
Synonyms :
venlafaxine
Class :
Serotonin-norepinephrine reuptake inhibitors
Brand Name :
Effexor, Effexor XR
Synonyms :
venlafaxine
Class :
Serotonin-norepinephrine reuptake inhibitors
Dosage forms& StrengthsÂ
Capsules/ extended releaseÂ
37.5mgÂ
75mgÂ
150mgÂ
TabletsÂ
25mgÂ
37.5mgÂ
50mgÂ
75mgÂ
100mgÂ
Tablets/ extended releaseÂ
37.5mgÂ
75mgÂ
112.5mgÂ
150mgÂ
225mgÂ
may have an increased tachycardic effect when combined with alpha-/beta-agonists
may have an increased tachycardic effect when combined with alpha-/beta-agonists
May have an increasingly adverse effect when combined with Serotonin/Norepinephrine Reuptake Inhibitors
may have an increased hepatotoxic effect when combined with serotonin/norepinephrine reuptake inhibitors
may have an increased tachycardic effect when combined with alpha-/beta-agonists
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may decrease the therapeutic effect when combined with Iobenguane Radiopharmaceutical Products
may increase the Qtc prolonging effect
may have an increased antiplatelet effect when combined with Abrocitinib
May have an increased serotonergic effect when combined with Serotonin/Norepinephrine Reuptake Inhibitors
may have an increased serotonergic effect when combined with Methylene Blue
May have an increased serotonergic effect when combined with Serotonin/Norepinephrine Reuptake Inhibitors
May have an increased serotonergic effect when combined with Serotonin/Norepinephrine Reuptake Inhibitors
May have an increased serotonergic effect when combined with Serotonin/Norepinephrine Reuptake Inhibitors
May have an increased serotonergic effect when combined with Serotonin/Norepinephrine Reuptake Inhibitors
May have an increased serotonergic effect when combined with Serotonin/Norepinephrine Reuptake Inhibitors
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may decrease the therapeutic effect when combined with Alpha2-Agonists
may decrease the therapeutic effect when combined with Alpha2-Agonists
may decrease the therapeutic effect when combined with Alpha2-Agonists
may decrease the therapeutic effect when combined with Alpha2-Agonists
may decrease the therapeutic effect when combined with Alpha2-Agonists
combining venlafaxine with ipratropium may increase the incidence or severity of tachycardia
venlafaxine may lower the excretion rate of n-acetyl tyrosine, potentially leading to higher serum levels
venlafaxine may raise the tachycardic activities of doxofylline
may have an increased serotonergic effect when combined with serotonin/norepinephrine reuptake inhibitors
may have an increased serotonergic effect when combined with serotonin/norepinephrine reuptake inhibitors
may have an increased serotonergic effect when combined with serotonin/norepinephrine reuptake inhibitors
may have an increased serotonergic effect when combined with serotonin/norepinephrine reuptake inhibitors
may have an increased serotonergic effect when combined with serotonin/norepinephrine reuptake inhibitors
fingolimod may enhance the QTc-prolonging effect of QT-prolonging Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
may enhance the QTc-prolonging effect of QT-prolonging Miscellaneous Agents
it enhances by affecting the hepatic enzyme CYP2D6 metabolism
it enhances by affecting the hepatic enzyme CYP2D6 metabolism
may enhance the Qtc prolonging effect
may increase the level of effectiveness through P-glycoprotein MDR1 efflux transporter
may enhance the QTc-prolonging effect of haloperidol
glycopyrrolate inhaled and formoterolÂ
may increase the QTc interval when combined
venlafaxine and azithromycin, if used in combination, increase the QTc interval
Actions and spectrum:Â
Venlafaxine acts by increasing the levels of the serotonin and norepinephrine in the brain through blockage of reuptake, that leads to an improvement in mood and a reduction in anxiety. It also has weak effects on dopamine and histamine systems and contribute to its antidepressant and anxiolytic effects.  Additionally, venlafaxine is known to have a pain-relieving effect, which is believed to be due to its modulation of the levels of neurotransmitters in the central nervous system. Â
Frequency defined Â
>10% Â
Headache  Â
Insomnia  Â
Asthenia  Â
Nausea  Â
Dizziness  Â
Ejaculation disorder  Â
Dry mouth Â
Somnolence  Â
Diaphoresis  Â
Nervousness  Â
Anorexia  Â
Anorgasmia Â
1-10% Â
Hypertension  Â
Impotence  Â
Weight loss  Â
Abnormal vision  Â
Paresthesia  Â
Vasodilation  Â
Vomiting  Â
Pruritus  Â
Yawning  Â
Weight gain  Â
Flatulence  Â
Mydriasis Â
Dyspepsia  Â
Twitching  Â
<1% Â
Angioedema Â
Anuria Â
Aneurism Â
Agranulocytosis Â
Anemia Â
Bacteremia Â
Myasthenia Â
Suicide ideation  Â
Syncope Â
Black box warningÂ
Never discontinue the medication without prior instructions from the doctor .
Contraindications/CautionÂ
DiabetesÂ
GlaucomaÂ
SeizureÂ
Bleeding problemsÂ
Lung diseaseÂ
Heart diseaseÂ
Liver diseaseÂ
Kidney diseaseÂ
Bipolar disorderÂ
Thyroid disorder
Pregnancy & breastfeeding:Â
Pregnancy consideration:Â
US FDA pregnancy category: CÂ
Breastfeeding warnings:Â
It should not be used in lactation as the drug is known to be excreted into human milk.Â
Pregnancy category:Â
Category A: well-controlled and satisfactory studies show no risk to the fetus in the first or later trimester.Â
Category B: There was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women.Â
Category C: There was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.Â
Category D: Adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.Â
Category X: Drugs listed in this category outweigh the risks over benefits. Hence, these categories of drugs need to be avoided by pregnant women.Â
Category N: No data for the drug under this category is available.Â
Pharmacology:Â
Venlafaxine belongs to the class of SNRIs (serotonin-norepinephrine reuptake inhibitors). It improves disorders associated with mood and symptoms of depression and anxiety. Â
Pharmacodynamics:Â
It is a potent inhibitor of the reuptake of serotonin and norepinephrine. It also weakly inhibits the reuptake of dopamine. By increasing the levels of these neurotransmitters in the brain, venlafaxine can modulate mood and reduce symptoms of depression and anxiety. This drug also has some effect on modulating pain signals in the brain and spinal cord, making it helpful in treating chronic pain conditions such as neuropathic pain. Â
Pharmacokinetics:Â
Absorption:Â Â
It is well absorbed following oral administration. Oral bioavailability is 45%. Time to reach peak plasma levels is 2 to 3 hours for immediate release tablets and 5.5 to 9 hours for extended-release tablets.Â
Distribution:Â
27 to 30% of the drug is bound to plasma proteins.Â
Volume of distribution of the drug is 7.5L/kgÂ
Metabolism:Â
The drug undergoes hepatic metabolism. It undergoes demethylation via CYP2D6 to O-desvenlafaxine, an active metabolite of venlafaxine. It also undergoes N-demethylation to form N-desmethylvenlafaxine through CYP2C19, CYP2C9 and CYP3A4.Â
Excretion:Â
87% of the drug is eliminated through urine in unchanged form. Â
Half-life:Â
5±2 hoursÂ
Administration:Â
Swallow the whole tablet or capsule. Do not chew it or crush.Â
Patient information leafletÂ
Generic Name: venlafaxineÂ
Pronounced: when-la-fax-inÂ
Why do we use venlafaxine?Â
venlafaxine is used to treat depression and anxiety including major depressive disorder (MDD), generalized anxiety disorder (GAD), social anxiety disorder (SAD), and panic disorder. It works by increasing the levels of serotonin and norepinephrine in the brain, which can improve mood and reduce symptoms of anxiety and depression. Â
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