Oxybutynin
DITROPAN
Pronunciation: ox-i-BYOO-ti-nin
“Ox’s booty in a (ditro)pan”
“Mad as a hatter” → BBB-crossing anticholinergic
What it isMuscarinic antagonist; overactive bladder.
Why this oneCheap, long-established, and available as a patch that avoids first-pass metabolism.
What limits itThe most anticholinergic of the bladder agents — confusion, dry mouth and constipation — and it crosses the blood-brain barrier, so avoid in dementia.
FDA-approved for
- overactive bladder (~1975)
Off-label
- hyperhidrosis
- hot flashes
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Overactive bladder / detrusor overactivity | Adults | 5 mg BID-TID | 5 mg BID-TID | 5 mg QID |
| Overactive bladder / detrusor overactivity | Frail elderly | 2.5 mg BID-TID | ||
| Overactive bladder / detrusor overactivity | Peds >5 yr | 5 mg BID | 5 mg BID | 5 mg TID |
Renal Undefined
Hepatic Undefined
Available strengths
- tab 2.5, 5 mg
- ER tab 5, 10, 15 mg
- sol 5 mg/5 mL
- patch 3.9 mg/24 hr
Contraindications
- Urinary retention
- Gastric retention or other severe decreased GI motility conditions
- Uncontrolled narrow-angle glaucoma (or at risk)
Cautions
- Anticholinergic effects (dry mouth, constipation)
- May aggravate urinary/gastric retention and narrow-angle glaucoma
- CNS effects (somnolence, dizziness, blurred vision)
- Heat prostration in hot environments
Adverse reactions
- Dry mouth (dose-related)
- Constipation
- Somnolence
- Dizziness
- Blurred vision
- Nausea
- Dyspepsia
Pregnancy Animal studies show no impaired fertility or fetal harm; safety in pregnant women not established
Lactation Undefined
Cost
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 2.5 mg | tab | 60 BID | $117.97 | not offered |
| 5 mg | tab | 60 BID | $2.88 | offered |
Other forms: Oxybutynin ER (DITROPAN XL)
Generic entry2014
NO BOXED WARNINGS
Principal riskAnticholinergic burden, worst of the bladder agents
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.
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