Should the Tricyclic Antidepressant Be Stopped?
Yes, discontinue the tricyclic antidepressant (TCA) immediately in this patient with urinary retention, as TCAs commonly cause anticholinergic adverse effects including urinary retention, and the patient is already on duloxetine (Cymbalta) which provides adequate antidepressant coverage without the same urinary retention risk. 1
Rationale for Stopping the TCA
TCAs and Urinary Retention Risk
- TCAs have well-established anticholinergic adverse effects including urinary retention, dry mouth, orthostatic hypotension, and constipation 1
- In patients with cardiac amyloidosis and neuropathic pain, guidelines specifically warn that tricyclic antidepressants may have increased side effects in patients with autonomic symptoms such as urinary retention 1
- A systematic review found that 17.6% of patients on imipramine (a TCA) experienced urinary retention, compared to only 0.1% when all TCAs were analyzed together, indicating significant risk 2
- The majority of case reports show improvement in urinary retention upon TCA discontinuation or dose reduction 2
Duloxetine Provides Adequate Coverage
- Duloxetine is already providing antidepressant therapy and is a first-line agent for major depressive disorder 3
- Importantly, duloxetine was not associated with urinary retention in 958 women treated in placebo-controlled trials 4
- In combined studies of 4,719 patients with depression and stress urinary incontinence, no cases of objective acute urinary retention requiring catheterization were reported with duloxetine 4
- While obstructive voiding symptoms occurred more often with duloxetine (1.0%) than placebo (0.4%), this is substantially lower than TCA risk 4
Polypharmacy Concerns
- Combining duloxetine with TCAs increases the risk of urinary retention through additive anticholinergic and adrenergic effects 5
- A case report documented urinary retention during combined treatment with duloxetine and another psychotropic medication, which resolved completely within one week after discontinuation 5
- The combination provides no additional benefit for depression management while substantially increasing adverse effect risk 2
Clinical Management Algorithm
Immediate Actions
- Discontinue the TCA immediately given active urinary retention symptoms 1, 2
- Continue duloxetine 60 mg daily as monotherapy for depression, as it provides dual serotonin-norepinephrine reuptake inhibition without significant urinary retention risk 3, 4
- Monitor voiding function closely for the next 1-2 weeks, as urinary retention typically resolves within one week of TCA discontinuation 5
If Urinary Retention Persists After TCA Discontinuation
- Reassess duloxetine's role, though this is unlikely given the low incidence of retention with duloxetine monotherapy 4
- Evaluate for other contributing medications including antipsychotics, antihistamines, or other anticholinergic agents 2
- Consider urological evaluation if retention persists beyond 2 weeks after TCA discontinuation 1
Depression Management Going Forward
- Duloxetine monotherapy at 60-120 mg daily is sufficient for major depressive disorder and avoids anticholinergic side effects 3
- SNRIs demonstrate superior efficacy to SSRIs for persistent pain if the patient has comorbid pain conditions 3
- Avoid reintroducing TCAs in this patient given the established causal relationship with urinary retention 1, 2
Common Pitfalls to Avoid
- Do not continue both medications hoping the urinary retention will spontaneously resolve—the anticholinergic burden is cumulative 5
- Do not switch to another TCA (such as nortriptyline or desipramine), as while secondary amines have lower anticholinergic effects, they still carry substantial urinary retention risk in a patient with active symptoms 1
- Do not add anticholinergic medications for overactive bladder symptoms if they develop, as this would worsen retention risk 1
- Do not assume urinary retention is solely due to benign prostatic hyperplasia without first addressing medication-induced causes 1