Major depressive disorder: The recommended dose for PRISTIQ is 50 mg once daily, with or without food. In clinical trials, doses of 50 to 400 mg/day were shown to be effective, although no additional benefit was demonstrated at doses greater than 50 mg/day. Based on clinical judgement, if dose increases are indicated for individual patient, they should occur gradually and at intervals of not less than 7 days. The maximum dose should not exceed 200 mg/day.
When discontinuing therapy, gradual dose reduction is recommended whenever possible to minimize discontinuation symptoms (see PRECAUTIONS).
PRISTIQ should be taken at approximately the same time each day. Tablets must be swallowed whole with fluid and not divided, crushed, chewed, or dissolved.
Use in patients with renal impairment: The recommended starting dose in patients with severe renal impairment (24-hr CrCl <30 mL/min) or end-stage renal disease (ESRD) is 50 mg every other day. Because of individual variability in clearance in these patients, individualization of dosage may be desirable. Supplemental doses should not be given to patients after dialysis (see PHARMACOLOGY: PHARMACOKINETICS under ACTIONS).
Use in patients with hepatic impairment: No dosage adjustment is necessary for patients with hepatic impairment (see PHARMACOLOGY: PHARMACOKINETICS under ACTIONS).
Pediatric use: Safety and effectiveness in patients less than 18 years of age have not been established.
Efficacy was not demonstrated in two adequate and well controlled, 8-week, randomized, double-blind, placebo-controlled, parallel group studies conducted in 587 patients (7 to 17 years of age) for the treatment of MDD.
Use in elderly patients: No dosage adjustment is required solely on the basis of age; however, possible reduced renal clearance of desvenlafaxine should be considered when determining dose (see PHARMACOLOGY: PHARMACOKINETICS under ACTIONS).
Greater sensitivity to desvenlafaxine in some older patients cannot be ruled out.
Discontinuing desvenlafaxine: Symptoms associated with discontinuation of desvenlafaxine, other SNRIs and SSRIs have been reported. Patients should be monitored for these symptoms when discontinuing treatment. A gradual reduction in the dose rather than abrupt cessation is recommended. If intolerable symptoms occur following a decrease in the dose or upon discontinuation of treatment, then resuming the previously prescribed dose may be considered. Subsequently, the physician may continue decreasing the dose, but at a more gradual rate (see ADVERSE REACTIONS). In some patients, discontinuation may need to occur over periods of months or longer.
Switching patients from other antidepressants to desvenlafaxine: Discontinuation symptoms have been reported when switching patients from other antidepressants, including venlafaxine, to desvenlafaxine. Tapering of the initial antidepressant may be necessary to minimize discontinuation symptoms.
Use of desvenlafaxine with reversible MAOIs such as linezolid or methylene blue: Do not start PRISTIQ in a patient who is being treated with a reversible MAOI such as linezolid or in whom intravenous methylene blue has been administered because there is increased risk of serotonin syndrome. In a patient who requires more urgent treatment of a psychiatric condition, non-pharmacological interventions, including hospitalization, should be considered (see CONTRAINDICATIONS).
In some cases, a patient already receiving PRISTIQ therapy may require urgent treatment with linezolid or intravenous methylene blue. If acceptable alternatives to linezolid or intravenous methylene blue treatment are not available and the potential benefits of linezolid or intravenous methylene blue treatment are judged to outweigh the risks of serotonin syndrome in a particular patient, PRISTIQ should be stopped promptly, and linezolid or intravenous methylene blue can be administered. The patient should be monitored for symptoms of serotonin syndrome for two weeks or until 24 hours after the last dose of linezolid or intravenous methylene blue, whichever comes first. Therapy with PRISTIQ may be resumed 24 hours after the last dose of linezolid or intravenous methylene blue (see PRECAUTIONS).
The risk of administering methylene blue by non-intravenous routes (such as oral tablets or by local injection) or in intravenous doses much lower than 1 mg/kg with PRISTIQ is unclear. The clinician should, nevertheless, be aware of the possibility of emergent symptoms of serotonin syndrome with such use (see PRECAUTIONS).