Oxybutynin

DITROPAN

Open Oxybutynin in the interactive console ↗

Pronunciation: ox-i-BYOO-ti-nin

Oxybutynin ballicule: receptor binding, kinetics and half-life diagram — Mechanism of action: Oxybutynin ballicule

Oxybutynin DITROPAN mascot mnemonic cartoon — Visual mnemonic: Oxybutynin mascot
**“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.

Pearls

ER better tolerated than IR; the preferred oral form.
Patch and gel: better tolerated but less effective than oral.
Patch available OTC (Oxytrol for Women).
Off-label for hot flashes, including breast cancer survivors.

Oxybutynin molecular structure (skeletal formula) — Molecular structure: Oxybutynin

Oxybutynin prescription history

Animated chart of estimated U.S. prescriptions per year, Overactive bladder meds (1970–2026). Oxybutynin enters in 1975 (estimated).

FDA-approved for

overactive bladder (~1975)

Off-label

hyperhidrosis
hot flashes

Principal riskAnticholinergic burden, worst of the bladder agents

Classes and tags

Clinical profile

Therapeutic safety burden1 / 4

Overdose danger1 / 4

Weight-gain liability0 / 4

Sedation liability1 / 4

QT / Torsades0 / 4

Direct muscarinic antagonism4 / 4

Embryofetal risk1 / 4

Legacy pregnancy categoryC

Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.

FDA label

Read the full label on DailyMed ↗

NO BOXED WARNINGS

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

Oxybutynin (DITROPAN)

What pharmacies pay · NADAC 9/30/26

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

Open Oxybutynin in the interactive console ↗

Memory aids: interaction avatars

CYP3A4 substrate

Open Oxybutynin in the interactive console ↗

Self-check

Oxybutynin: Which formulation avoids first-pass metabolism?
The patch.
Oxybutynin: Why avoid it in dementia?
It crosses the blood-brain barrier and can cause confusion.