Lafactin (Venlafaxine)

• Venlafaxine acts on the serotonin and norepinephrine pathways and is indicated for several mood and anxiety disorders.
• Major depressive disorder: alleviates depressive symptoms and improves functional outcomes.
• Generalized anxiety disorder: reduces excessive worry and associated physical tension.
• Social anxiety disorder: diminishes fear of social situations and improves interpersonal functioning.
• Panic disorder: lowers the frequency and severity of panic attacks.

• Venlafaxine inhibits the reuptake of serotonin and norepinephrine at therapeutic doses, increasing their concentrations in the synaptic cleft. At higher doses it also modestly blocks dopamine reuptake. This combined neurotransmitter enhancement restores mood balance and reduces anxiety by modulating central nervous system signaling pathways.

Venlafaxine may cause a range of adverse reactions, varying in frequency and severity.

Common Side Effects

• Nausea
• Headache
• Dry mouth
• Insomnia
• Dizziness
• Sweating

Serious or Rare Side Effects

• Elevated blood pressure or hypertension
• Serotonin syndrome (confusion, hyperthermia, muscle rigidity)
• Severe hyponatremia (low sodium levels)
• Suicidal thoughts or behavior, especially early in treatment
• Severe skin reactions (e.g., Stevens‑Johnson syndrome)
• Cardiac arrhythmias or QT prolongation

• When prescribing venlafaxine, clinicians should consider several safety precautions.
• Blood pressure monitoring: check regularly as the drug can raise systolic and diastolic pressure.
• Suicidality risk: monitor for worsening depression or emergence of suicidal thoughts, especially early in treatment.
• Serotonin syndrome: avoid concomitant serotonergic agents and watch for symptoms such as agitation, hyperreflexia, and fever.
• Hyponatremia: assess serum sodium in at‑risk patients, particularly the elderly.
• Pregnancy category: use only if the potential benefit justifies the potential risk to the fetus.
• Store at below 25°C: keep in the original container, protect from moisture and light.

Venlafaxine interacts with several drug classes; some combinations require avoidance while others need close monitoring.

Major Interactions (Avoid)

• Monoamine oxidase inhibitors (MAOIs): risk of hypertensive crisis and serotonin syndrome.
• Other serotonergic agents (e.g., SSRIs, tramadol): heightened serotonin syndrome risk.
• St. John’s wort: may increase serotonergic activity.
• Thioridazine: can cause QT prolongation.
• Linezolid: potent serotonergic effect.

Moderate Interactions (Monitor Closely)

• NSAIDs and anticoagulants: increased bleeding risk.
• Antihypertensives: venlafaxine may attenuate blood‑pressure‑lowering effect.
• CYP2D6 inhibitors (e.g., fluoxetine, paroxetine): may raise venlafaxine plasma levels.
• Alcohol: may enhance central nervous system depression.
• Lithium: monitor for additive serotonergic effects.