Onelar (Duloxetine)

Duloxetine is an SNRI that addresses several central nervous system and pain pathways.

• Major depressive disorder: alleviates depressive symptoms and improves mood.
• Generalized anxiety disorder: reduces anxiety and associated physical tension.
• Diabetic peripheral neuropathic pain: lessens nerve‑related pain in the feet and legs.
• Fibromyalgia: decreases widespread musculoskeletal pain and fatigue.
• Chronic musculoskeletal pain: provides relief from chronic low‑back and osteoarthritis pain.

• Duloxetine inhibits the reuptake of serotonin and norepinephrine at neuronal synapses, increasing the concentration of these neurotransmitters in the central nervous system. The enhanced serotonergic and noradrenergic signaling modulates mood, anxiety, and pain perception pathways, contributing to its antidepressant and analgesic effects.

Duloxetine may cause a range of adverse reactions, from mild to severe.

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Dry mouth: reduced salivation.
• Headache: intermittent tension‑type headache.
• Insomnia: difficulty falling or staying asleep.
• Sweating: increased perspiration.
• Dizziness: light‑headed sensation, especially when standing.

Serious or Rare Side Effects

• Hepatotoxicity: elevated liver enzymes or liver injury.
• Hypertensive crisis: sudden, severe increase in blood pressure.
• Serotonin syndrome: agitation, hyperthermia, tremor, and confusion.
• Suicidal thoughts: emergence or worsening of suicidal ideation.
• Severe skin reactions: Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Orthostatic hypotension: marked drop in blood pressure upon standing.

When prescribing Duloxetine, clinicians should evaluate patient history and monitor for specific risks.

• Hepatic function: assess liver enzymes before initiating therapy.
• Cardiovascular status: monitor blood pressure and heart rate regularly.
• Concomitant serotonergic drugs: avoid combined use that may trigger serotonin syndrome.
• Renal impairment: adjust monitoring in patients with reduced kidney function.
• Pregnancy and lactation: weigh benefits against potential risks; use only if clearly needed.
• Store at ambient temperature: keep below 25°C, in the original container, protected from moisture and direct sunlight.

Duloxetine interacts with several medication classes; careful review is essential.

Major Interactions (Avoid)

• Monoamine oxidase inhibitors (MAOIs): risk of hypertensive crisis and serotonin syndrome.
• Strong CYP1A2 inhibitors (e.g., fluvoxamine): may increase duloxetine plasma levels.
• Serotonergic opioids (e.g., tramadol): heightened risk of serotonin syndrome.

Moderate Interactions (Monitor Closely)

• NSAIDs and antiplatelet agents: increased bleeding tendency.
• CYP2D6 substrates (e.g., metoprolol): possible altered metabolism.
• Antihypertensives: potential additive blood‑pressure‑lowering effect.