Citalopram Dosing in Adults
For adult patients with depression, citalopram (Celexa) should be initiated at 20 mg once daily, with a maximum recommended dose of 40 mg daily. 1, 2
Initial Dosing
- Start with 10-20 mg once daily, with 20 mg being the standard starting dose for most adults 1
- Lower starting doses (10 mg daily) may be appropriate for patients who are elderly, have hepatic impairment, or are known CYP2C19 poor metabolizers 2
- Citalopram can be taken in the morning or evening with no significant difference in efficacy 1
Dose Titration
- If needed, increase dose after 1-2 weeks of treatment based on clinical response 1
- Dose increases should be made in increments of 10-20 mg 1
- Allow at least 1 week between dose adjustments to assess for side effects due to the long half-life (approximately 35 hours) 2
Maximum Dosing
- Maximum recommended dose is 40 mg daily for most adults 1, 2
- For patients over 60 years of age, maximum dose should not exceed 20 mg daily due to increased risk of QT prolongation 2
- For patients with hepatic impairment, maximum dose should not exceed 20 mg daily 2
- For CYP2C19 poor metabolizers, maximum dose should not exceed 20 mg daily 2
- For patients taking concomitant CYP2C19 inhibitors (e.g., cimetidine, omeprazole), maximum dose should not exceed 20 mg daily 2
Special Populations
- Elderly patients (>60 years): Maximum dose of 20 mg daily due to 30-50% increase in drug exposure and half-life compared to younger adults 2
- Hepatic impairment: Maximum dose of 20 mg daily due to reduced clearance (37%) and doubled half-life 2
- Renal impairment: Consider dose reduction in moderate renal impairment; oral clearance reduced by 17% 2
- Pregnancy: Decision to use during pregnancy should be made on a case-by-case basis, weighing risks of untreated depression against potential risks of medication 2
Efficacy Considerations
- Clinical response may take 4-8 weeks to fully manifest 1
- Although 10 mg daily may show some antidepressive effect, 20-40 mg daily doses typically show greater efficacy 3, 4
- Patients with more severe depression may benefit from higher doses within the recommended range 1, 3
Duration of Treatment
- Continue treatment for 4-12 months after remission of a first depressive episode 1
- Longer treatment duration may be beneficial for patients with recurrent depression 1
- When discontinuing, taper gradually over 10-14 days to minimize withdrawal symptoms 1
Side Effects and Monitoring
- Common side effects include nausea, sleep disturbances, sweating, tremors, nervousness, dizziness, and sexual dysfunction 1
- Monitor for QT prolongation, especially at higher doses or in at-risk patients 2
- Citalopram is generally well-tolerated compared to other antidepressants 1
- Fatal overdoses are rare but possible with massive ingestions 5
Common Pitfalls to Avoid
- Exceeding maximum recommended doses (40 mg for adults, 20 mg for elderly/hepatic impairment/CYP2C19 poor metabolizers) 2
- Abrupt discontinuation (can cause withdrawal symptoms) 1
- Failure to recognize drug interactions with CYP2C19 inhibitors 2
- Inadequate duration of treatment (should continue for months after symptom resolution) 1
- Underestimating the time needed to see full clinical response (4-8 weeks) 1