Are Detrol and Ditropan the Same Thing?
No, Detrol (tolterodine) and Ditropan (oxybutynin) are not the same medication—they are two different antimuscarinic drugs used to treat overactive bladder, though they belong to the same therapeutic class and work through similar mechanisms.
Key Differences Between the Two Medications
Chemical Structure and Selectivity
- Tolterodine (Detrol) demonstrates functional selectivity for bladder muscarinic receptors over salivary glands compared to oxybutynin (Ditropan), which translates into a more favorable side effect profile 1, 2.
- Both are competitive muscarinic receptor antagonists, but their tissue selectivity profiles differ significantly 3.
Clinical Efficacy
- Both medications show equivalent efficacy for treating overactive bladder symptoms 4, 1.
- In pooled analyses, tolterodine 2 mg twice daily and oxybutynin 5 mg three times daily produced equivalent reductions in micturition frequency (-2.3 and -2.0 vs -1.4 placebo) and urge incontinence episodes (-1.6 and -1.8 vs -1.1 placebo) 1.
- Extended-release tolterodine 4 mg once daily resulted in 70% of patients perceiving improved bladder condition compared to 60% with extended-release oxybutynin 10 mg 5.
Tolerability Profile—The Critical Distinction
- The most important clinical difference is tolerability, particularly regarding dry mouth 1, 2.
- Tolterodine produces significantly lower incidence (40% vs 78%, p < 0.001) and intensity of dry mouth compared to oxybutynin 1.
- Fewer patients discontinue tolterodine due to adverse effects: 12% withdrawal rate with tolterodine ER 4 mg versus 21% with oxybutynin ER 10 mg (p = 0.002) 5.
- The AUA/SUFU guidelines recommend transdermal oxybutynin preparations if dry mouth is a concern with oral antimuscarinics 4.
Guideline Recommendations for Selection
Both Are Equally Acceptable Second-Line Options
- The AUA/SUFU guidelines list both oxybutynin and tolterodine (along with darifenacin, fesoterodine, solifenacin, and trospium) as equivalent second-line therapies after behavioral interventions fail 4.
- No hierarchy is implied among these antimuscarinic options in terms of efficacy 4.
- The European Association of Urology similarly recommends both agents as acceptable oral antimuscarinic options 6.
Shared Side Effect Profile
Both medications share common antimuscarinic adverse effects including 4, 6:
- Dry mouth (most common)
- Constipation
- Dry eyes and blurred vision
- Dyspepsia
- Urinary tract infection
- Urinary retention
- Impaired cognitive function
Shared Contraindications
Both medications are contraindicated in 4:
- Narrow-angle glaucoma (unless approved by ophthalmologist)
- Impaired gastric emptying
- History of urinary retention
- Patients using solid oral potassium chloride
Clinical Decision-Making Algorithm
When to Choose Tolterodine Over Oxybutynin
- Patients particularly concerned about dry mouth severity 1, 5
- Patients who previously discontinued oxybutynin due to intolerable anticholinergic effects 3
- Patients requiring long-term therapy where tolerability affects adherence 2
When to Choose Oxybutynin Over Tolterodine
- Cost is a primary concern, as oxybutynin is significantly less expensive 3
- Transdermal formulations are preferred to minimize systemic side effects 4
Critical Safety Measure Before Initiating Either Medication
- Check post-void residual volume in patients at risk for urinary retention (men with lower urinary tract symptoms, suspected bladder outlet obstruction) 7, 8.
- Obtain clearance from specialists for patients with gastric emptying problems or urinary retention risk 4.
Common Clinical Pitfall
The most frequent error is failing to distinguish that while these medications are therapeutically equivalent in efficacy, tolterodine's superior tolerability profile may improve long-term adherence 1, 5. The choice should be guided by individual patient tolerability concerns and cost considerations rather than efficacy expectations, as both produce similar symptom improvements 4, 9.