Duloxetine Hydrochloride
Brand Name: Cymbalta
Generic Available
Dosage Forms:
Capsules: 20 mg, 30 mg, 60 mg
FDA Indications/Dosages:
For the treatment of major depressive disorder (MDD): The normal total daily dose is 40-60 mg. A 40 mg daily dose should be given as 20 mg twice a day. A 60 mg daily dose may be given as 30 mg twice a day or 60 mg once a day.
For the management of neuropathic pain associated with diabetic peripheral neuropathy: 60 mg per day.
For the treatment of generalized anxiety disorder (GAD): Start with 30 mg daily for 1 week and then increase to 60 mg daily. Maximum daily dose is 120 mg.
For the management of chronic musculoskeletal pain: Start with 30 mg daily for 1 week then increase to 60 mg daily.
If the choice to discontinue duloxetine is made, a gradual reduction of dose rather than abrupt cessation is recommended. At least 14 days should elapse between discontinuation of a monoamine oxidase inhibitor and initiation of duloxetine. At least 5 days should elapse before starting an MOAI after discontinuing duloxetine.
Pharmacology/Pharmacokinetics: Duloxetine is a potent inhibitor of neuronal serotonin and norepinephrine reuptake and a slight inhibitor of dopamine reuptake. Its mechanism of action is thought to be due to a potentiation of serotonergic and noradrenergic activity in the CNS. Duloxetine is well absorbed orally with peak plasma concentrations reached in 6 hours. Food slightly delays the time to peak plasma levels and decreases amount absorbed by 10%. Evening doses delay absorption by 3 hours and increase apparent clearance of duloxetine by 30%. Metabolism occurs via many pathways, including hepatic isoenzymes CYP2D6 and CYP1A2. Elimination half-life is approximately 12 hours and steady-state levels are reached in 3 days.
Drug Interactions: Serious and sometimes fatal reactions have occurred in patients taking a serotonin reuptake inhibitor with MONOAMINE OXIDASE INHIBITORS. Potents inhibitors of CYP1A2 (fluvoxamine, quinolones) and CYP2D6 (paroxetine, fluoxetine, quinidine) will increase plasma levels of duloxetine. Plasma levels of drugs metabolized by CYP2D6 (tricyclic antidepressants, phenothiazines, propafenone, and flecainide) may be increased when used with duloxetine.
Contraindications/Precautions: ANTIDEPRESSANTS INCREASE SUICIDAL THOUGHTS AND ACTIONS IN CHILDREN, ADOLESCENTS, AND YOUNG ADULTS. Use is contraindicated in patients taking monoamine oxidase inhibitors and in patients with uncontrolled narrow-angle glaucoma. Patients being treated with antidepressants should be observed closely for clinically worsening and suicidality, especially at the beginning of therapy, or at the time of dose changes. Use with caution in patients with impaired hepatic function and in patients with heavy alcohol use. Duloxetine may increase blood pressure and active mania/hypomania in some individuals; use appropriate precautions. Use with caution in patients with a history of seizures or controlled narrow-angle glaucoma. Do not use late into the third trimester. Nursing is not recommended while on duloxetine. Pregnancy Category C.
Adverse Effects: Adverse effects occurring in more than 2% of the population include nausea (20%), dry mouth (15%), constipation (11%), insomnia (11%), dizziness (9%), diarrhea (8%), decreased appetite (8%), fatigue (8%), drowsiness (7%), sweating (6%), vomiting (5%), blurred vision (4%), and erectile dysfunction (4%).
Patient Consultation:
Therapeutic effects may take as long as 4 weeks to appear.
May cause drowsiness. Use caution while operating machinery or when mental alertness is required.
Avoid alcohol while taking this medication.
Consult your physician or pharmacist before taking nonprescription medications.
Do not abruptly discontinue medication.
Store in a cool, dry place away from sunlight and children.
Contact a physician if the above side effects are severe or persistent.
If a dose is missed, skip it and return to normal dosing schedule.
Pay close attention to any changes, especially sudden changes, in mood behaviors, thoughts, or feelings. Antidepressants may increase suicidal thoughts or feelings.
Continued therapy of up to 2 weeks may be needed to show noticeable improvement.












