DOSAGE AND ADMINISTRATION Citalopram Oral Solution, USP should be administered once daily, in the morning or evening, with or without food. Initial Treatment Citalopram Oral Solution, USP should be administered at an initial dose of 20 mg once daily, with an increase to a maximum dose of 40 mg/day at an interval of no less than one week. Doses above 40 mg/day are not recommended due to the risk of QT prolongation. Additionally, the only study pertinent to dose response for effectiveness did not demonstrate an advantage for the 60 mg/day dose over the 40 mg/day dose. Special Populations 20 mg/day is the maximum recommended dose for patients who are greater than 60 years of age, patients with hepatic impairment, and for CYP2C19 poor metabolizers or those patients taking cimetidine or another CYP2C19 inhibitor ( see WARNINGS ). No dosage adjustment is necessary for patients with mild or moderate renal impairment. Citalopram Oral Solution, USP should be used with caution in patients with severe renal impairment. Treatment of Pregnant Women During the Third Trimester Neonates exposed to Citalopram Oral Solution, USP and other SSRIs or SNRIs, late in the third trimester, have developed complications requiring prolonged hospitalization, respiratory support, and tube feeding ( see PRECAUTIONS ). When treating pregnant women with Citalopram Oral Solution, USP during the third trimester, the physician should carefully consider the potential risks and benefits of treatment. Maintenance Treatment It is generally agreed that acute episodes of depression require several months or longer of sustained pharmacologic therapy. Systematic evaluation of Citalopram Oral Solution, USP in two studies has shown that its antidepressant efficacy is maintained for periods of up to 24 weeks following 6 or 8 weeks of initial treatment (32 weeks total). In one study, patients were assigned randomly to placebo or to the same dose of Citalopram Oral Solution, USP (20 to 60 mg/day) during maintenance treatment as they had received during the acute stabilization phase, while in the other study, patients were assigned randomly to continuation of Citalopram Oral Solution, USP 20 or 40 mg/day, or placebo, for maintenance treatment. In the latter study, the rates of relapse to depression were similar for the two dose groups ( see CLINICAL PHARMACOLOGY ; Clinical Efficacy Trials ). Based on these limited data, it is not known whether the dose of citalopram needed to maintain euthymia is identical to the dose needed to induce remission. If adverse reactions are bothersome, a decrease in dose to 20 mg/day can be considered. Discontinuation of Treatment with Citalopram Oral Solution, USP Symptoms associated with discontinuation of Citalopram Oral Solution, USP and other SSRIs and SNRIs have been reported ( see PRECAUTIONS ). Patients should be monitored for these symptoms when discontinuing treatment. A gradual reduction in the dose rather than abrupt cessation is recommended whenever possible. 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. Switching Patients To or From a Monoamine Oxidase Inhibitor (MAOI) Intended to Treat Psychiatric Disorders At least 14 days should elapse between discontinuation of an MAOI intended to treat psychiatric disorders and initiation of therapy with Citalopram Oral Solution, USP. Conversely, at least 14 days should be allowed after stopping Citalopram Oral Solution, USP before starting an MAOI intended to treat psychiatric disorders ( see CONTRAINDICATIONS ). Use of Citalopram Oral Solution, USP with Other MAOIs, Such as Linezolid or Methylene Blue Do not start Citalopram Oral Solution, USP in a patient who is being treated with linezolid or intravenous methylene blue because there is an increased risk of serotonin syndrome. In a patient who requires more urgent treatment of a psychiatric condition, other interventions, including hospitalization, should be considered ( see CONTRAINDICATIONS ). In some cases, a patient already receiving Citalopram Oral Solution, USP 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, Citalopram Oral Solution, USP should be stopped promptly, and linezolid or intravenous methylene blue can be administered. The patient should be monitored for symptoms of serotonin syndrome for 2 weeks or until 24 hours after the last dose of linezolid or intravenous methylene blue, whichever comes first. Therapy with Citalopram Oral Solution, USP may be resumed 24 hours after the last dose of linezolid or intravenous methylene blue ( see WARNINGS ). 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 Citalopram Oral Solution, USP is unclear. The clinician should, nevertheless, be aware of the possibility of emergent symptoms of serotonin syndrome with such use ( see WARNINGS ).