Onelar (Duloxetine)

Duloxetine acts on serotonin and norepinephrine pathways to treat several mood and pain disorders.

• Major depressive disorder: reduces depressive symptoms and improves overall mood.
• Generalized anxiety disorder: alleviates excessive worry and anxiety.
• Diabetic peripheral neuropathic pain: lessens nerve‑related pain in diabetes.
• Fibromyalgia: decreases widespread musculoskeletal pain and fatigue.
• Chronic musculoskeletal pain: provides relief from persistent back or joint pain.

• Duloxetine inhibits the reuptake of the neurotransmitters serotonin and norepinephrine at neuronal synapses, thereby increasing their extracellular concentrations. The enhanced serotonergic and noradrenergic signaling modulates mood, anxiety and pain pathways, contributing to its therapeutic effects in depression, anxiety and various chronic pain states.

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Dry mouth: reduced salivation causing discomfort.
• Constipation: slowed intestinal motility.
• Dizziness: sensation of light‑headedness.
• Somnolence: increased sleepiness.
• Increased sweating: excessive perspiration.

Serious or Rare Side Effects

• Suicidal thoughts: emergence of suicidal ideation, especially early in treatment.
• Serotonin syndrome: potentially life‑threatening condition with agitation, hyperthermia, and neuromuscular abnormalities.
• Severe liver injury: jaundice or hepatitis.
• Hyponatremia: low blood sodium causing confusion.
• Severe rash or Stevens‑Johnson syndrome.
• Elevated blood pressure: significant hypertension requiring medical attention.

Before initiating therapy, clinicians should evaluate patient history and monitor for specific risks.

• Assess for suicidal ideation: monitor mood changes closely.
• Avoid use in uncontrolled narrow‑angle glaucoma: may increase intra‑ocular pressure.
• Use caution in hepatic impairment: dose adjustment may be required.
• Do not discontinue abruptly: taper under medical supervision to avoid withdrawal.
• Pregnancy Category C: weigh potential benefits against risks.
• Store at room temperature: keep in original packaging, protect from moisture and direct sunlight.

Duloxetine may interact with several drug classes, requiring careful management.

Major Interactions (Avoid)

• Monoamine oxidase inhibitors (MAOIs): risk of serotonin syndrome.
• Thioridazine: may cause cardiac arrhythmias.
• Linezolid: increased serotonergic activity.
• Strong CYP1A2 inhibitors (e.g., fluvoxamine): may raise duloxetine levels.
• Alcohol: enhances central nervous system depression.

Moderate Interactions (Monitor Closely)

• Other serotonergic agents (SSRIs, SNRIs, triptans): monitor for serotonin syndrome.
• NSAIDs or aspirin: increased bleeding risk.
• CYP2D6 inhibitors (e.g., quinidine): may elevate plasma concentrations.
• Antihypertensives: duloxetine can raise blood pressure.
• Anticoagulants: potential for enhanced anticoagulant effect.