Dosing and uses of Celexa (citalopram)
Adult dosage forms and strengths
tablet
- 10mg
- 20mg
- 40mg
oral solution
- 10mg/5mL
Depression
Depression in patients whose diagnosis corresponds most closely to the DSM-III and DSM-III-R category of major depressive disorder
Initial dose: 20 mg PO qDay
If needed, may increase to 40 mg/day after at least 1 week
Doses above 40 mg/day are not recommended, because of risk for QT prolongation without additional benefit for treating depression
Dosing Modifications
Poor CYP2C19 metabolizers or coadministration with CYP2C19 inhibitors (eg, cimetidine, fluconazole, omeprazole): Do not exceed 20 mg/day
Hepatic impairment decreases clearance and therefore increases risk of QT prolongation; do not exceed 20 mg/day
MAO inhibitors
- Not for administration within 14 days of administering a MAO inhibitor
Linezolid or Methylene Blue Therapy
- Not for administration to patients that are receiving linezolid or IV methylene blue; consider other forms of therapy; if therapy required and benefits outweigh risks discontinue citalopram therapy, administer linezolid or methylene blue and monitor for serotonin syndrome for 2 weeks or 24 hr after last dose of linezolid or methylene blue
Renal impairment
- Mild to moderate renal impairment: No dosage adjustment required
- Severe renal impairment (CrCl <20 mL/min): Not studied; use with caution
Alcoholism (Off-label)
20-40 mg PO qDay
Binge-eating Disorder (Off-label)
20-60 PO qDay
Generalized Anxiety Disorder (Off-label)
Initial: 10 mg PO qDay; may titrate to 40 mg/day
Panic Disorder (Off-label)
20 mg PO qDay initially; after 1 week, may increase to 40 mg/day if warranted
Not to exceed 40 mg/day because of increased risk for QT prolongation
Hot Flashes (Off-label)
Initial: 10 mg PO qDay; may increase to 20 mg/day after 1 week
Obsessive-Compulsive Disorder (Off-label)
Initial: 20 mg PO qDay; may titrate to 40-60 mg/day; improvement may be seen 4-6 weeks after initiating therapy
Premenstrual Dysphoric Disorder (Off-label)
5 mg PO on the estimated day of ovulation; increase dose by 5 mg each day thereafter to maximum 30 mg; continue thereafter until menstruation begins; decrease dose to 20 mg on the first day of menstruation; the next day, decrease to 10 mg; stop the treatment from day 3 until ovulation begins
Pediatric dosage forms and strengths
tablet
- 10mg
- 20mg
- 40mg
oral solution
- 10mg/5mL
Depression (Off-label)
<12 years
- 10 mg PO qDay; may increase by 5 mg/day every 2 weeks to 40 mg PO qDay; doses >40 mg not recommended (may increase risk of QT prolongation)
≥12 years
- 20 mg PO qDay; may increase by 10 mg/day every 2 weeks to 40 mg PO qDay; doses >40 mg not recommended (may increase risk of QT prolongation)
Impulsive Aggresive Behavior (Off-label)
10 mg PO qDay; titrate by 10 mg/week, as tolerated to maximum 40 mg/day
Geriatric dosage forms and strengths
Depression
>60 years: Do not exceed 20 mg PO qDay
Dosing Considerations
-The elderly are more prone to SSRI/SNRI-induced hyponatremia and risk for QT prolongation
Celexa (citalopram) adverse (side) effects
>10%
Dry mouth (20%)
Nausea (21%)
Somnolence (18%)
Insomnia (15%)
Xerostomia (20%)
Increased sweating (11%)
1-10%
Tremor (8%)
Diarrhea (8%)
Ejaculation disorder (6%)
Rhinitis (5%)
Upper respiratory infection (5%)
Dyspepsia (5%)
Fatigue (5%)
Vomiting (4%)
Anxiety (4%)
Anorexia (4%)
Abdominal pain (3%)
Agitation (3%)
Impotence (3%)
Sinusitis (3%)
Dysmenorrhea (3%)
Decreased libido (2%)
Yawning (2%)
Arthralgia (2%)
Myalgia (2%)
Amenorrhea (>1%)
Confusion (>1%)
Cough (>1%)
Flatulence (>1%)
Increased saliva (>1%)
Migraine (>1%)
Orthostatic hypotension (>1%)
Paresthesia (>1%)
Polyuria (>1%)
Pruritus (>1%)
Rash (>1%)
Tachycardia (>1%)
Weight change (>1%)
Warnings
Black box warnings
In short-term studies, antidepressants increased the risk of suicidal thinking and behavior in children, adolescents, and young adults (<24 years) taking antidepressants for major depressive disorders and other psychiatric illnesses
This increase was not seen in patients >24 years; a slight decrease in suicidal thinking was seen in adults >65 years
In children and young adults, the risks must be weighed against the benefits of taking antidepressants
Patients should be monitored closely for changes in behavior, clinical worsening, and suicidal tendencies; this should be done during initial 1-2 months of therapy and dosage adjustments
The patient’s family should communicate any abrupt changes in behavior to the health-care provider
Worsening behavior and suicidal tendencies that are not part of the presenting symptoms may require discontinuation of therapy
Not FDA approved for the treatment of bipolar disorder
This drug is not FDA approved for use in pediatric patients
Contraindications
Hypersensitivity
Coadministration with pimozide
Coadministration with serotonergic drugs
- Concomitant use or within 14 days of MAOIs increases risk of serotonin syndrome
- Symptoms include tremor, myoclonus, diaphoresis, nausea, vomiting, flushing, dizziness, hyperthermia with features resembling neuroleptic malignant syndrome, seizures, rigidity, autonomic instability with possible rapid fluctuations of vital signs, and mental status changes that include extreme agitation progressing to delirium and coma
- Starting citalopram in a patient who is being treated with linezolid or IV methylene blue is contraindicated because of an increased risk of serotonin syndrome
- If linezolid or IV methylene blue must be administered, discontinue SSRI immediately and monitor for CNS toxicity; may resume 24 hr after last linezolid or methylene blue dose, or after 2 weeks of monitoring (5 weeks for fluoxetine), whichever comes first
Cautions
Pregnancy: Conflicting evidence regarding use of SSRIs during pregnancy and increased risk of persistent pulmonary hypertension of the newborn, or PPHN (see Pregnancy)
Neonates exposed to SNRIs/SSRIs late in third trimester: Risk of complications such as feeding difficulties, irritability, and respiratory problems
Clinical worsening and suicide ideation may occur despite medication in adolescents and young adults (18-24 years)
Risk of mydriasis; may trigger angle closure attack in patients with angle closure glaucoma with anatomically narrow angles without a patent iridectomy
Risk of hyponatremia, abnormal bleeding (increased if concomitant aspirin, NSAIDs, or anticoagulants, or hemorrhagic diathesis), and impairment of cognitive and motor functions
Risk of serotonin syndrome or neuroleptic malignant syndrome (NMS)-like reactions have been reported with SSRIs alone or with concomitant use of serotonergic drugs, with drugs that impair metabolism of serotonin, or with antipsychotics or other dopamine antagonists
Activation of mania/hypomania has been reported; use caution when treating patients with history of mania
Increased risk of bone fractures reported with antidepressant use; use caution; consider possibility of fracture it patient presents with bone pain
May cause or exacerbate sexual dysfunction
Use caution when treating patients with history of seizure disorder
Rare cases of hyponatremia and development of SIADH reported with either SSRI or SNRI use
Not recommended in patients with uncompensated heart failure
QT prolongation
- Dose-dependent QT prolongation reported; do not exceed dose of 40 mg/day
- Correct hypokalemia and hypomagnesemia before initiating and monitor periodically
- ECG monitoring recommended in patients with CHF, bradyarrhythmias, or concomitant medications known to prolong QT interval
- Do not exceed 20 mg/day if administered in CYP2C19 poor metabolizers, or in patients taking concomitant cimetidine or another CYP2C19 inhibitor (eg, fluconazole, omeprazole)
- Do not exceed 20 mg/day in individuals aged 60 yr or older, or those with hepatic impairment
Pregnancy and lactation
Pregnancy
Pregnancy category: C
Use late in the third trimester associated with complications in newborns and may require prolonged hospitalization, respiratory support, and tube feeding
Persistent pulmonary hypertension of the newborn
- Potential risk of PPHN when used during pregnancy
- Initial public health advisory, in 2006, was based on a single published study; since then, there have been conflicting findings from new studies, making it unclear whether use of SSRIs during pregnancy can cause PPHN
- FDA has reviewed the additional new study results and has concluded that, given the conflicting results from different studies, it is premature to reach any conclusion about a possible link between SSRI use in pregnancy and PPHN
- FDA recommendation: FDA advises health care professionals not to alter their current clinical practice of treating depression during pregnancy and to report any adverse events to the FDA MedWatch program
- A meta-analysis of 7 observational studies, found exposure to SSRIs in late pregnancy (ie, >20 weeks' gestation) more than doubled the risk of PPHN that could not be explained by other etiologies (eg, congenital malformations, meconium aspiration) (BMJ 2014;348:f6932)
Lactation
Excreted in breast milk; use caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Celexa (citalopram)
Mechanism of action
Inhibits the reuptake of serotonin in presynaptic neurons; little or no affinity for dopamine, alpha-adrenergic histamine, or cholinergic receptor
Absorption
Bioavailability: 80%
Peak serum time: 1-6 hr (4 hr average)
Onset: 1-4 weeks for depression; full response may not be seen until 8-12 weeks after initiating treatment
Distribution
Protein bound: 80%
Vd: 12 L/kg
Metabolism
Mainly via hepatic P450 enzymes CYP3A4 and CYP2C19
Metabolites: Insignificant potency
Elimination
Half-life: 24-48 hr
Dialyzable: No
Renal clearance: 66 mL/min
Total body clearance: 330 mL/min
Excretion: Urine (10%)
