In Citalopram (escitalopram)-induced hypomania, can Citalopram be reduced and Lithium started on the same day?

Management of Citalopram-Induced Hypomania

In citalopram-induced hypomania, you should gradually taper the citalopram (not abruptly discontinue) while simultaneously initiating lithium on the same day, provided appropriate monitoring capabilities are available.

Immediate Management Strategy

Citalopram Tapering Approach

• Gradual tapering of SSRIs is essential to avoid withdrawal symptoms and prevent rebound worsening of symptoms 1.
• The FDA drug label specifically warns that families and caregivers should monitor for "hypomania, mania, other unusual changes in behavior" and that "such symptoms may be associated with an increased risk for suicidal thinking and behavior and indicate a need for very close monitoring and possibly changes in the medication" 2.
• Do not abruptly stop citalopram - abrupt discontinuation of antidepressants can lead to withdrawal effects and potentially worsen mood instability 1.

Lithium Initiation

• Lithium can be started on the same day as you begin tapering citalopram, as there are no significant pharmacokinetic interactions between these medications 2.
• The FDA label states: "Coadministration of citalopram tablets (40 mg/day for 10 days) and lithium (30 mmol/day for 5 days) had no significant effect on the pharmacokinetics of citalopram or lithium" 2.
• However, caution is warranted: "Because lithium may enhance the serotonergic effects of citalopram, caution should be exercised when citalopram tablets and lithium are coadministered" 2.

Practical Implementation

Day 1 Actions

• Begin lithium at 150 mg/day (appropriate starting dose for mood stabilization) 1.
• Reduce citalopram dose (e.g., if on 20-40 mg, reduce by 50% initially rather than stopping completely) 1.
• Ensure monitoring capabilities are in place - lithium should only be initiated "in those settings where personnel and facilities for close clinical and laboratory monitoring are available" 1.

Monitoring Requirements

• Baseline laboratory assessment before lithium: complete blood count, thyroid function tests, urinalysis, blood urea nitrogen, creatinine, serum calcium, and pregnancy test in females 1.
• Monitor for serotonin syndrome given the potential for lithium to enhance serotonergic effects of citalopram during the overlap period 2.
• Daily monitoring for worsening hypomania/mania during the transition period 2.
• Plasma lithium levels should be monitored with appropriate dose adjustments 2.

Evidence-Based Rationale

Why Gradual Taper is Critical

• Case reports demonstrate that escitalopram-induced hypomania is dose-related, with symptoms emerging after dose increases and subsiding with dose reductions 3.
• Historical evidence shows that abrupt tricyclic antidepressant withdrawal can precipitate hypomania/mania within 2-7 days 4.
• The key principle: "prescribers are generally encouraged to taper medication slowly to avoid withdrawal symptoms (e.g., benzodiazepines or SSRIs) or rebound worsening of symptoms" 1.

Why Lithium is Appropriate

• WHO guidelines recommend that "lithium, valproate, or carbamazepine should be offered to individuals with bipolar mania" 1.
• When antidepressants are used in bipolar depression, they should "always in combination with a mood stabilizer (lithium or valproate)" 1.
• A pilot study showed that one patient with citalopram-induced hypomania responded to treatment adjustments 5.

Common Pitfalls to Avoid

• Do not abruptly discontinue citalopram - this increases risk of withdrawal symptoms and mood destabilization 1.
• Do not delay mood stabilizer initiation - the hypomania requires immediate treatment with appropriate mood stabilization 1.
• Do not start lithium without proper monitoring capabilities - lithium requires close clinical and laboratory monitoring 1.
• Do not ignore the possibility of underlying bipolar disorder - antidepressant-induced mood elevation may unmask bipolar disorder requiring diagnostic reassessment 1, 6.

Taper Schedule Consideration

• Week 1: Reduce citalopram by 50% while starting lithium 150 mg/day.
• Week 2: Further reduce citalopram by another 50% (now at 25% of original dose) while titrating lithium based on levels and response.
• Week 3-4: Complete citalopram discontinuation while optimizing lithium dosing to achieve therapeutic levels (0.2-0.6 mEq/L may be adequate) 1.