Duloxetine

Oral
Anxiety

Oral
Diabetic neuropathy

Oral
Depression

Oral
Fibromyalgia

Mild to moderate: Consider lower starting dose and titrate dose gradually. Severe: Avoid use.

Avoid use.

May be taken with or without food. Swallow whole, do not chew/crush.

Hepatic impairment, severe renal impairment, uncontrolled HTN or narrow-angle glaucoma. Concomitant use w/ MAOIs or w/in 14 days of discontinuing the MAOI. Use w/ linezolid or IV methylene blue. Concomitant use w/ potent CYP1A2 inhibitors (e.g. ciprofloxacin, enoxacin).

Patient w/ HTN, gastroparesis, mania or hypomania, increased intraocular pressure or at risk of acute narrow-angle glaucoma, seizure, bleeding disorders, mild to moderate renal impairment. Smokers. Gradual dose reduction is recommended rather than abrupt withdrawal. Pregnancy and lactation.

Changes in behaviour, suicidal ideation, HTN, headache, somnolence, fatigue, dizziness, insomnia, agitation, tremor, anxiety, insomnia, lethargy, abnormal dreams, nausea, xerostomia, palpitation, hyperhydrosis, decreased libido, hot flushes, sexual dysfunction, vomiting, constipation, diarrhoea, dyspepsia, abdominal pain, wt gain, decreased appetite, erectile dysfunction, increased hepatic enzymes, muscle spasms, paraesthesia, tinnitus, blurred vision, mydriasis, nasopharyngitis, hyponatraemia, may impair platelet aggregation. Stevens-Johnson syndrome and erythema multiforme.
Potentially Fatal: Hepatic failure w/ or w/o jaundice.

PO: C

May impair ability to drive or operate machinery.

Monitor BP and mental status for depression. Closely observe for clinical worsening, suicidality and unusual changes in behaviour.

Symptoms: Somnolence, coma, serotonin syndrome, seizures, vomiting and tachycardia. Management: Ensure adequate airway, oxygenation and ventilation. Initiate gastric lavage immediately after ingestion. Admin activated charcoal to reduce absorption. Monitor cardiac rhythm and vital signs.

Increased risk of serotonin syndrome w/ TCA, SSRI, SNRI, lithium. May increase bleeding risk w/ aspirin, NSAIDs, warfarin and other anticoagulants.
Potentially Fatal: Increased risk of serotonin syndrome w/ MAOIs, linezolid and methylene blue. Increased serum levels and risk of toxicity w/ potent CYP1A2 inhibitors (e.g. ciprofloxacin, enoxacin).

Increased risk of serotonin syndrome w/ St John’s wort. Increased risk of hepatic injury w/ alcohol.

Description: Duloxetine is a potent inhibitor of neuronal reuptake of serotonin, norepinephrine and to a lesser extent dopamine. It has no significant affinity for adrenergic, muscarinic, cholinergic, histaminergic, opioid, glutamate and GABA receptors. It also does not inhibit monoamine oxidase.
Pharmacokinetics:
Absorption: Well absorbed from GI tract. Bioavailability: Between 32-80%. Time to peak plasma concentration: Approx 6 hr.
Distribution: - Distributed into breast milk. Plasma protein binding: Approx 96% mainly to albumin and α₁-acid glycoprotein.
Metabolism: Extensively metabolised by CYP1A2 and CYP2D6 isoenzymes.
Excretion: Via urine and faeces (approx 20%). Elimination half-life: 8-17 hr.

Store below 30°C.

Antidepressants / Anxiolytics / Drugs for Neuropathic Pain

Anon. Duloxetine. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 24/07/2014.

Buckingham R (ed). Duloxetine Hydrochloride. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 24/07/2014.

Duloxetine Capsule, Delayed Release (Remedyrepack Inc.). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 24/07/2014.

McEvoy GK, Snow EK, Miller J et al (eds). Duloxetine Hydrochloride. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 24/07/2014.