Oxybutynin ER
DITROPAN XL
Pronunciation: ox-i-BYOO-ti-nin
“Ox’s booty in a (ditro)pan”
“Mad as a hatter” → BBB-crossing anticholinergic
What it isOxybutynin extended-release (DITROPAN XL, 1998) antagonizes muscarinic and H1 receptors; overactive bladder.
Why this oneIts apparent half-life ~13 h (vs ~2 h IR) smooths exposure and reduces dry mouth versus immediate release.
What limits itDry mouth, constipation, urinary retention, and cognitive impairment give it the heaviest anticholinergic burden among bladder drugs.
FDA-approved for
- overactive bladder (1998)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Overactive bladder (urge urinary incontinence, urgency, frequency) | Adults | 5 or 10 mg PO once daily | 30 mg/day | |
| Detrusor overactivity associated with a neurological condition (e.g., spina bifida) | Peds ≥6 yr | 5 mg PO once daily | 20 mg/day |
Titration Adjust in 5 mg increments, generally at ~weekly intervals
Renal Undefined
Hepatic Undefined
Instructions
- Swallow whole with liquid; do not chew, divide, or crush
- May be taken with or without food
- Not recommended in children who cannot swallow the tablet whole or under age 6
Available strengths
- ER tab 5, 10, 15 mg
- tab 2.5, 5 mg
- sol 5 mg/5 mL
- patch 3.9 mg/24 hr
Contraindications
- Urinary retention
- Gastric retention and other severe decreased gastrointestinal motility conditions
- Uncontrolled narrow-angle glaucoma
Cautions
- Angioedema (may occur after the first dose)
- Anticholinergic CNS effects (hallucinations, agitation, confusion, somnolence)
- Aggravation of symptoms in dementia on cholinesterase inhibitors, Parkinson's disease, myasthenia gravis
- Decreased GI motility in autonomic neuropathy
- Urinary retention with bladder outflow obstruction
- GI obstructive disorders / GERD
Adverse reactions
- Dry mouth
- Constipation
- Diarrhea
- Headache
- Somnolence
- Dizziness
- Blurred vision
Pregnancy No adequate data on use in pregnant women
Lactation No data on presence in human milk or effects on the breastfed infant
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 5 mg | ER tab | 30 qd | $2.52 | offered |
| 10 mg | ER tab | 30 qd | $2.99 | offered |
| 15 mg | ER tab | 30 qd | $3.75 | offered |
Other forms: Oxybutynin (DITROPAN)
NO BOXED WARNINGS
Principal riskAnticholinergic burden, worst of the bladder agents
Classes and tags
Clinical profile
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