Oxybutynin is a medication primarily used to treat overactive bladder and urinary incontinence. It belongs to a class of drugs called anticholinergics, which work by relaxing the bladder muscles to reduce urinary urgency and frequency. Oxybutynin can help control symptoms such as frequent urination, urgency, and leakage.

Oxybutynin (Ditropan) is an anticholinergic (antimuscarinic) drug that is used to treat overactive bladder manifesting s urinary urgency, frequency, and incontinence.

Oxybutynin Uses:

Overactive bladder:

• Used for treatment of symptoms associated with overactive bladder (eg, urge urinary incontinence, urgency, frequency, urinary leakage, dysuria).
• Used for treatment of symptoms associated with overactive bladder due to a neurological condition (eg, spina bifida) in patients ≥6 years of age (extended-release tablet only).

Off Label Use of Oxybutynin in Adults:

• Primary focal hyperhidrosis

Oxybutynin Dose in Adults

Oxybutynin Dose in the treatment of Overactive bladder (urinary urgency with or without incontinence):

For oral use:

• Extended-release tablets: Start with 5 to 10 mg once a day, and adjust the dose by 5 mg increments every 1 to 2 weeks as needed. The maximum dose is 30 mg once a day.
• Immediate-release tablets: Start with 5 mg, 2 to 3 times a day. Adjust the dose by 5 mg increments every 1 to 2 weeks as needed. The maximum dose is 5 mg, 4 times a day. For people with certain nerve-related bladder issues, a lower starting dose may be considered.
• For nighttime urination (nocturia), some experts suggest 2.5 to 5 mg once daily at bedtime may be enough.

For topical gel:

• Apply the contents of one sachet or one pump actuation once a day.

For transdermal use:

• Apply one 3.9 mg patch twice a week, changing it on the same two days each week.

For over-the-counter use (patient-guided therapy):

• Females can apply one 3.9 mg patch every 4 days.

It's important to follow the prescribed dosage and adjust it according to your doctor's instructions. The full effects of the medication may take several weeks to be noticed, so be patient and continue treatment as directed.

Oxybutynin Dose in the treatment of primary focal hyperhidrosis as an alternative agent (off-label): Oral:

• Extended-release tablets: Take 5 to 10 mg once daily.
• Immediate-release tablets: Start with a low dose of 2.5 mg once daily, then gradually increase the dose as needed and tolerated. The typical effective dose range is 5 to 10 mg per day, split into two doses.

It's important to follow your doctor's instructions carefully when using oxybutynin for primary focal hyperhidrosis. Be aware of any side effects and let your doctor know if you experience any concerns or adverse reactions.

Oxybutynin Dose in Childrens

Oxybutynin Dose in the treatment of Neurogenic and Overactive bladder:

For immediate-release tablets:

• For infants and children up to 5 years old: Limited data suggests a dosage of 0.1 to 0.2 mg/kg per dose, given 2 to 3 times daily. The maximum dose per individual dose is 5 mg. In some cases, doses as high as 0.2 mg/kg per dose every 6 hours have been reported.
• For children older than 5 years and adolescents: Start with 5 mg twice daily and increase as needed, up to 5 mg three times daily. The maximum dose for adults is 5 mg four times daily.

For extended-release tablets:

• For children 6 years and older and adolescents: Begin with 5 mg once daily and adjust the dose as necessary, in 5 mg increments, with weekly intervals. The maximum daily dose is 20 mg.

Oxybutynin Intravesical Dose: Limited data available:

• For infants, children, and adolescents: The recommended dose is 0.2 mg per kilogram of body weight per dose, given twice daily at intervals of 8 to 12 hours. The maximum dose per individual dose is 5 mg.

It's important to note that data on intravesical use of oxybutynin is limited, and dosing recommendations may vary based on individual patient factors and the specific condition being treated.

Oxybutynin dose in the treatment of Idiopathic Overactive bladder: Transdermal:

Children aged 4 years and older:

• Apply one 3.9 mg/day patch twice weekly, with patches changed every 3 to 4 days.
• This dosing regimen is based on a retrospective study involving 35 children with idiopathic overactive bladder.
• In this study, most patients (97%) reported good symptom control.
• However, skin irritation at the application site was reported in 35% of patients, with 20% discontinuing therapy due to this side effect.
• No other significant side effects were reported.

Pregnancy Risk Factor B

• Oxybutynin is classified as Pregnancy Risk Factor B, which means that no adverse events were observed in animal studies regarding its effects on pregnancy.
• However, there's limited information available about its use in pregnant individuals treated for neurogenic bladder.
• So, it's important for pregnant individuals to discuss the potential risks and benefits of using oxybutynin with their healthcare provider before starting or continuing treatment.

Oxybutynin use during breastfeeding:

• The presence of oxybutynin in breast milk is not known for certain.
• Therefore, individuals who are breastfeeding should carefully consider the potential risks of infant exposure to oxybutynin.
• It's essential to weigh these risks against the benefits of breastfeeding to the infant as well as the benefits of treatment to the mother.
• Additionally, there have been reports of oxybutynin causing suppression of lactation.

Oxybutynin Dose in Kidney Disease:

• The manufacturer's labeling for oxybutynin does not provide specific dosage adjustments for individuals with renal impairment, as this aspect has not been thoroughly studied.
• Therefore, it's crucial to exercise caution when prescribing oxybutynin to patients with renal impairment.

Oxybutynin Dose in Liver Disease:

• In the manufacturer's labeling for oxybutynin, no specific dosage adjustments are provided for individuals with hepatic impairment, as this aspect has not been thoroughly studied.
• Therefore, it's essential to proceed with caution when prescribing oxybutynin to patients with hepatic impairment.

Common Side Effects of Oxybutynin:

• Central Nervous System:
  • Dizziness
  • Drowsiness
• Gastrointestinal:
  • Xerostomia
  • Constipation
  • Nausea
• Local:
  • Application Site Pruritus

Less Common Side Effects Of Oxybutynin:

• Cardiovascular:
  • Decreased Blood Pressure
  • Edema
  • Flushing
  • Increased Blood Pressure
  • Palpitations
  • Peripheral Edema
  • Sinus Arrhythmia
• Central Nervous System:
  • Headache
  • Nervousness
  • Insomnia
  • Confusion
  • Falling
  • Flank Pain
  • Pain
  • Fatigue
• Dermatologic:
  • Macular Eruption
  • Xeroderma
  • Pruritus
• Endocrine & Metabolic:
  • Fluid Retention
  • Increased Thirst
  • Increased Serum Glucose
• Gastrointestinal:
  • Diarrhea
  • Dyspepsia
  • Coated Tongue
  • Eructation
  • Upper Abdominal Pain
  • Flatulence
  • Abdominal Pain
  • Dysgeusia
  • Viral Gastroenteritis
  • Vomiting
  • Gastroesophageal Reflux Disease
• Genitourinary:
  • Urinary Hesitancy
  • Urinary Tract Infection
  • Urinary Retention
  • Cystitis
  • Pollakiuria
  • Increased Postvoid Residual Urine Volume
  • Dysuria
• Infection:
  • Fungal Infection
• Local:
  • Application Site Erythema
  • Application Site Reaction
  • Application Site Rash
  • Application Site Vesicles
  • Application Site Dermatitis
• Neuromuscular & Skeletal:
  • Arthralgia
  • Back Pain
  • Limb Pain
  • Asthenia
• Ophthalmic:
  • Blurred Vision
  • Eye Irritation
  • Keratoconjunctivitis Sicca
  • Visual Disturbance
  • Xerophthalmia
• Respiratory:
  • Dry Nose
  • Upper Respiratory Tract Infection
  • Asthma
  • Bronchitis
  • Hoarseness
  • Nasal Congestion
  • Nasopharyngitis
  • Paranasal Sinus Congestion
  • Pharyngolaryngeal Pain
  • Sinus Headache
  • Cough
  • Dry Throat
  • Oropharyngeal Pain

Contraindications to Oxybutynin:

• Oxybutynin should not be used in individuals who have a known hypersensitivity to oxybutynin or any component of the formulation.
• It is also contraindicated in patients with or at risk for uncontrolled narrow-angle glaucoma, urinary retention, gastric retention, or conditions with severely decreased gastrointestinal motility.
• When used over-the-counter, it's important not to use oxybutynin if experiencing pain or burning during urination, blood in the urine, unexplained lower back or side pain, cloudy or foul-smelling urine, or if male, under the age of 18 years, experiencing only accidental urine loss when coughing, sneezing, or laughing, diagnosed with urinary or gastric retention, glaucoma, or if there's a known hypersensitivity to oxybutynin.
• In Canadian labeling, additional contraindications include severe gastrointestinal conditions and myasthenia gravis.
• It's important for individuals to discuss any existing conditions or concerns with their healthcare provider before using oxybutynin.

Warnings and precautions

Hypersensitivity reactions and angioedema:

• Oxybutynin can sometimes cause allergic reactions, including severe ones like anaphylaxis and angioedema, which involves swelling in areas like the face, lips, tongue, and throat.
• In some cases, this swelling can happen even after just one dose.
• If swelling occurs in the tongue, throat, or larynx, it's crucial to stop taking oxybutynin right away and seek medical help immediately for proper treatment.

CNS effects

• Anticholinergic medications like oxybutynin can sometimes lead to effects on the central nervous system (CNS), such as agitation, confusion, drowsiness, dizziness, hallucinations, headache, sleepiness, or blurred vision.
• These effects can impair both physical and mental abilities.
• Patients should be warned about performing tasks that need mental alertness, like operating machinery or driving, while taking oxybutynin.
• If these CNS effects occur, it's important to consider reducing the dose or stopping the medication altogether.

Heat prostration:

• Oxybutynin may raise the risk of heat prostration, a condition where the body overheats.
• It's essential to be cautious in hot weather or situations where there's a risk of overheating.
• If you experience symptoms like fever, excessive sweating, or feeling faint in hot conditions, it's crucial to seek cooler surroundings and hydrate yourself.

Bladder flow obstruction

• Oxybutynin should be used cautiously in patients with bladder flow obstruction because it could potentially increase the risk of urinary retention.

Cardiovascular disease

• Oxybutynin should be used with caution in patients who have cardiovascular disease, including coronary artery disease (CAD), heart failure, hypertension, or cardiac arrhythmias.
• This medication may potentially worsen these conditions.

Dementia

• Oxybutynin should be used cautiously in patients with dementia who are also being treated with cholinesterase inhibitors.
• There is a risk that oxybutynin may worsen symptoms of dementia.
• It's important for patients and caregivers to monitor for any changes in cognitive function or behavior while using oxybutynin.

GI disorders

• Oxybutynin should be used carefully in patients with gastrointestinal (GI) disorders, particularly those with decreased GI motility or obstructive disorders, as it may increase the risk of gastric retention.
• Caution is advised in patients with conditions such as ulcerative colitis, intestinal atony, pyloric stenosis, gastroesophageal reflux, or those taking medications that can cause or worsen esophagitis (such as bisphosphonates).
• In patients with ulcerative colitis, oxybutynin use may reduce gastric motility, potentially raising the risk of paralytic ileus or toxic megacolon.

Glaucoma:

• Oxybutynin should be used cautiously in patients with treated angle-closure glaucoma, as it may worsen the condition.
• However, it is contraindicated in individuals with uncontrolled narrow-angle glaucoma.

Hepatic impairment

• Oxybutynin should be used cautiously in patients with hepatic impairment due to limited experience with this population.

Hiatal hernia

• Oxybutynin should be used cautiously in patients with hiatal hernia.
• While oxybutynin primarily affects the bladder, there's a potential risk of gastrointestinal side effects, such as acid reflux, which may exacerbate symptoms of hiatal hernia.

Hyperthyroidism:

• Oxybutynin should be used cautiously in patients with hyperthyroidism, a condition where the thyroid gland produces too much thyroid hormone.
• Oxybutynin might exacerbate symptoms related to hyperthyroidism.

Myasthenia gravis:

• Oxybutynin should be avoided in patients with myasthenia gravis, a neuromuscular disorder that causes muscle weakness, as it may worsen the condition.
• If signs or symptoms of myasthenia gravis occur while taking oxybutynin, therapy should be discontinued.

Neuropathy:

• Oxybutynin should be used cautiously in patients with autonomic neuropathy, a condition affecting the nerves that control involuntary bodily functions, as it may worsen symptoms of decreased gastrointestinal (GI) motility.

Parkinson disease

• Oxybutynin should be used cautiously in patients with Parkinson's disease, a progressive nervous system disorder, as it may worsen symptoms of the disease.

Prostatic hyperplasia, urinary stricture

• Oxybutynin should be used cautiously in patients with prostatic hyperplasia (enlarged prostate) and/or urinary stricture, as it may lead to urinary retention.

Renal impairment

• Oxybutynin should be used cautiously in patients with renal impairment due to limited experience with this population.

Monitoring Parameters:

Incontinence Episodes:

• Oxybutynin is used to treat incontinence, but it's important to monitor if it's effectively reducing episodes of accidental urine leakage.

Postvoid Residual (PVR):

• This refers to the amount of urine left in the bladder after urination.
• Oxybutynin may affect bladder emptying, so it's essential to check PVR to ensure the bladder is properly emptying.

Anticholinergic Reactions:

• Oxybutynin belongs to a group of drugs called anticholinergics, which can cause side effects like dry mouth, constipation, and dizziness.
• These reactions should be monitored and managed appropriately.

How to administer Oxybutynin?

Oral Extended-Release Tablets:

• Administer without regard to meals.
• Swallow whole with liquid; do not crush, divide, or chew.
• Take at approximately the same time each day.

Topical Gel:

• For topical use only.
• Apply to clean, dry, intact skin on abdomen, thighs, or upper arms/shoulders.
• Rotate application sites; do not apply to the same site on consecutive days.
• Wash hands after use.
• Cover treated area with clothing after gel has dried to prevent transfer of medication to others.
• Wait 1 hour after applying gel before bathing, showering, or swimming.
• Avoid applying to recently shaved skin.

Transdermal Patch:

• Apply to clean, dry, smooth (fold-free) skin on abdomen, hip, or buttock.
• Do not apply to areas treated with oils, lotions, or powders.
• Avoid areas with cuts, scrapes, or other irritation (i.e., rashes).
• Do not cut the patch.
• Apply each system at a new site (avoid reapplication to the same site within 7 days).
• Contact with water during bathing, swimming, showering, or exercising will not affect efficacy, but avoid rubbing the patch area during these activities.
• Wear under clothing; avoid exposure to sunlight.

Mechanism of action of Oxybutynin:

• Oxybutynin has a direct antispasmodic effect on smooth muscle, meaning it helps relax these muscles.
• It also works by blocking the action of acetylcholine, a neurotransmitter involved in muscle contractions.
• This blocking effect is similar to atropine, but oxybutynin has 4 to 10 times the antispasmodic activity.
• Importantly, oxybutynin doesn't interfere with skeletal muscle or autonomic ganglia.
• It helps increase bladder capacity, reduce uncontrolled contractions, and delay the urge to urinate.
• By doing so, it decreases the urgency and frequency of urination.

Onset of Action:

• Oral Immediate Release: Takes 30 to 60 minutes to start working.

Peak Effect:

• Immediate Release: Reaches its highest effect in 3 to 6 hours.
• Extended Release: Peaks after 3 days.

Duration:

• Oral Immediate Release: Lasts for 6 to 10 hours.
• Extended Release: Works for up to 24 hours.
• Transdermal: Effective for 96 hours.

Absorption:

• Oral: Gets into the bloodstream quickly and efficiently.
• Transdermal: Absorbs well through the skin.

Distribution:

• IV Volume of Distribution: Approximately 193 liters.

Protein Binding:

• Binds to over 99% of proteins, mainly alpha-1 acid glycoprotein.

Metabolism:

• Takes place primarily in the liver via an enzyme called CYP3A4.
• Oral form experiences significant metabolism when it first passes through the liver, resulting in both active and inactive byproducts.

Bioavailability:

• Oral Immediate Release: About 6%, with some variability (range: 1.6% to 10.9%).

Half-life Elimination:

• IV: Around 2 hours for the parent drug, and 7 to 8 hours for its metabolites.
• Oral Immediate Release: Lasts about 2 to 3 hours.
• Extended Release: Persists for approximately 13 hours.
• Transdermal: Stays in the body for about 64 hours.

Time to Peak, Serum:

• Oral Immediate Release: Takes roughly 60 minutes to reach its highest level in the blood.
• Extended Release: Peaks between 4 to 6 hours.
• Transdermal: Reaches its peak after 24 to 48 hours.

Excretion:

• Mostly eliminated through urine, with less than 0.1% excreted as both metabolites and unchanged drug.

International Brands of Oxybutynin:

• Ditropan XL
• Gelnique
• Gelnique Pump
• Oxytrol
• Oxytrol For Women
• APO-Oxybutynin
• Ditropan XL
• DOM-Oxybutynin
• Gelnique
• MYLAN-Oxybutynin
• Oxytrol
• PHLOxybutynin
• PMS-Oxybutynin
• RIVA-Oxybutynin
• TEVA-Oxybutynin
• Ao Ning
• Butyn
• Contimax
• Cystrin
• Delifon
• Detronin
• Ditropan
• Ditropan XL
• Diutropan
• Dresplan
• Dridase
• Driptane
• Frenurin
• Gradual
• Inprax
• Kentera
• Kentera Patch
• Lenditro
• Lyrinel
• Lyrinel Oros SR
• Lyrinel XL
• Mutum
• Mutum CR
• Nefryl
• Neoxy Tape
• Newin
• Novitropan
• Obutin
• Odranal
• Oxurate
• Oxyban
• Oxyspas
• Oxytrol
• Pollakisu
• Reteven
• Sibutin
• Socliden
• Tavor
• Tropan
• Uricon CR
• Urihexal
• Uroflax
• Uropan
• Uroxal

Oxybutynin Brand Names in Pakistan:

Oxybutynin 3 mg Tablets
Butyn	Figs Pharmaceuticals
Oxitrin	Dr. Raza Pharma (Private) Limited
Oxynin	Venus Pharma
Taivor	Raazee Theraputics (Pvt) Ltd.

 

Oxybutynin 5 mg Tablets
Cystrin	A.J. & Company.
Oxitrin	Dr. Raza Pharma (Private) Limited
Oxityn	Rakaposhi Pharmaceutical (Pvt) Ltd.
Oxycystin	Pulse Pharmaceuticals
Oxynin-5	Venus Pharma