Inactive ingredients: 

Oxybin Scored Tablets:

Microcrystalline cellulose PH 101, maize starch, sodium starch glycolate, magnesium stearate, lactose monohydrate, aerosil 200.

Oxybin Syrup:

Citric acid anhydrous, sodium citrate anhydrous, sucrose, sorbitol 70% solution, methylparaben, sucralose, sodium cyclamate, glycerol, purified water.

Urinary incontinence, urgency and frequency in the unstable bladder, whether due to neurogenic bladder disorders (detrusor hyperreflexia) in conditions such as multiple sclerosis and spina bifida, or to idiopathic detrusor instability (motor urge incontinence).

Pediatric population:

Oxybin is indicated in Children over 5 years of age for:

Urinary incontinence, urgency and frequency in unstable bladder conditions due to idiopathic overactive bladder or neurogenic bladder disorders (detrusor overactivity).

Nocturnal enuresis associated with detrusor overactivity, in conjunction with nondrug therapy, when other treatment has failed.

Dosage:

Adults:

The usual dose is 5 mg (5 ml) two or three times a day. This may be increased to a maximum of 5 mg (5 ml) four times a day to obtain a clinical response provided that the side effects are tolerated.

Elderly (including Frail Elderly):

The elimination half-life is increased in the elderly. Therefore, a dose of 2.5 mg (2.5 ml) twice a day, particularly if the patient is frail, is likely to be adequate.

This dose may be titrated upwards to 5 mg (5 ml) twice a day to obtain a clinical response provided that the side effects are tolerated.

Pediatric population:

Children (Under 5 years of age):

Not recommended.

Children (Over 5 years of age):

Neurogenic Bladder Instability:

The usual dose is 2.5 mg (2.5 ml) twice a day. This dose may be titrated upwards to 5 mg (5 ml) two or three times a day to obtain a clinical response provided that the side effects are tolerated.

Nocturnal Enuresis:

The usual dose is 2.5 mg (2.5 ml) twice a day. This dose may be titrated upwards to 5 mg (5 ml) two or three times a day to obtain a clinical response provided that the side effects are tolerated. The last dose should be given before bedtime.

Administration:

For Oral administration.

Hypersensitivity to oxybutynin or to any of the excipients.

Myasthenia gravis.

Narrow-angle glaucoma or shallow anterior chamber.

Gastrointestinal obstruction including paralytic ileus and intestinal atony.

Patients with toxic megacolon or severe ulcerative colitis.

Patients with bladder outflow obstruction where urinary retention may be precipitated.

Oxybin should be used with caution in the frail elderly, patients with Parkinson’s disease and children who are at greater risk of occurrence of adverse reactions to the product and in patients with autonomic neuropathy (such as those with Parkinson’s disease), severe gastro-intestinal motility disorders, hepatic or renal impairment.

Anticholinergics should be used with caution in elderly patient’s due to the risk of cognitive impairment.

Gastrointestinal disorders: Anticholinergic medicinal products may decrease gastrointestinal motility and should be used with caution in patients with gastrointestinal obstructive disorders, intestinal atony and ulcerative colitis.

Oxybutynin may aggravate tachycardia (and thus hyperthyroidism, congestive heart failure, coronary heart disease, cardiac arrhythmias, hypertension), cognitive disorders and symptoms of prostatic hypertrophy.

Anticholinergic CNS effects (e.g. hallucinations, agitation, confusion, somnolence) have been reported; monitoring is recommended, especially in first few months after initiating therapy or increasing the dose; consider discontinuing therapy or reducing the dose if anticholinergic CNS effects develop.

Since oxybutynin can cause narrow-angle glaucoma, patients should be advised to contact a physician immediately if they are aware of a sudden loss of visual acuity or ocular pain.

Oxybutynin may reduce salivary secretions which could result in dental caries, periodontitis or oral candidiasis.

Anticholinergic medicinal products should be used with caution in patients who have hiatus hernia/gastro-esophageal reflux and/or who are concurrently taking medicinal products (such as bisphosphonates) that can cause or exacerbate esophagitis.

When oxybutynin is used in high environmental temperatures, this can cause heat prostration due to decreased sweating.

Pediatric population:

The use of Oxybin in children under 5 years of age is not recommended; it has not been established whether oxybutynin can be safely used in this age group.

There is limited evidence supporting the use of oxybutynin in children with monosymptomatic nocturnal enuresis (not related to detrusor overactivity).

In children over 5 years of age, Oxybin should be used with caution, as they may be more sensitive to the effects of the product, particularly the CNS and psychiatric adverse reactions.

Excipients:

Oxybin Tablets contains lactose monohydrate. Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take Oxybin.

Care should be taken if other anticholinergic agents are administered together with Oxybin, as a potentiation of anticholinergic effects could occur.

The anticholinergic activity of oxybutynin is increased by concurrent use of other anticholinergics or medicinal products with anticholinergic activity, such as amantadine and other anticholinergic antiparkinsonian medicinal products (e.g. procyclidine, levodopa), antihistamines, antipsychotics (e.g. phenothiazines, butyrophenones, clozapine), quinidine, digitalis, tricyclic antidepressants, atropine and related compounds like antispasmodics and dipyridamole.

By reducing gastric motility, Oxybin may affect the absorption of other drugs.

Oxybutynin is metabolised by cytochrome P450 isoenzyme CYP 3A4.

Concomitant administration with a CYP3A4 inhibitor can inhibit oxybutynin metabolism and increase oxybutynin exposure.

Oxybutynin may antagonise prokinetic therapies.

Concomitant use with cholinesterase inhibitors may result in reduced cholinesterase inhibitor efficacy.

Patients should be informed that alcohol may enhance the drowsiness caused by anticholinergic agents such as oxybutynin.

Pregnancy:

There are no adequate data from the use of oxybutynin in pregnant women. Animal studies are insufficient with respect to effects on pregnancy, embryonic/fetal development, parturition or postnatal development. The potential risk for humans is unknown. Oxybin should not be used during pregnancy unless clearly necessary.

Lactation:

When oxybutynin is used during lactation, a small amount is excreted in the mother's milk. Use of Oxybin during lactation is therefore not recommended.

Oxybin may cause drowsiness or blurred vision. Patients should be cautioned regarding activities requiring mental alertness such as driving, operating machinery or performing hazardous work while taking this drug.

Adverse effects have been listed under headings of body systems and their frequencies as follows, where possible: Very common: (≥ 1/10); Common: (≥ 1/100 to <1/10); Uncommon: (≥ 1 /1,000 to <1/100); Rare :(≥ 1/10, 000 to <1/1,000); Very rare: (<1/10,000), Not known: (cannot be estimated from the available data).

Infections and Infestations:

Not known: Urinary tract infection.

Gastrointestinal disorders:

Very common: Constipation, nausea, dry mouth.

Common: Diarrhea, vomiting.

Uncommon: Abdominal discomfort, anorexia, decreased appetite, dysphagia.

Not known: Gastroesophageal reflux disease, pseudo-obstruction in patients at risk (elderly or patients with constipation and treated with other drugs that decrease intestinal motility).

Psychiatric disorders:

Common: Confusional state.

Not known: Agitation, anxiety, hallucinations, nightmares, paranoia, cognitive disorders in elderly, symptoms of depression, dependence to oxybutynin (in patients with history of drug or substance abuse).

Nervous system disorders:

Very common: Dizziness, headache, somnolence.

Not known: Cognitive disorders, convulsions, drowsiness, disorientation.

Cardiac disorders:

Not known: Tachycardia, arrhythmia.

Injury, Poisoning and Procedural complications:

Not known: Heat stroke.

Eye disorders:

Very common: Blurred vision.

Common: Dry eyes.

Not known: Angle closure glaucoma, mydriasis, ocular hypertension.

Renal and Urinary disorders:

Common: Urinary retention.

Not known: Difficulty in micturition.

Vascular disorders:

Common: Flushing (which may be more marked in children).

Skin and Subcutaneous tissue disorders:

Very common: Dry skin.

Not known: Angioedema, rash, urticaria, hypohidrosis, photosensitivity.

Immune system disorders:

Not known: Hypersensitivity.

The symptoms of overdose with oxybutynin progress from an intensification of the usual side effects of CNS disturbances (from restlessness and excitement to psychotic behavior), circulation changes (flushing, fall in blood pressure, circulatory failure etc.), respiratory failure, paralysis and coma.

Measures to be taken are:

1) Immediate gastric lavage.

2) Physostigmine by slow intravenous injection.

Adults: 

0.5 to 2.0 mg of physostigmine by slow intravenous administration. Repeat after 5 minutes, if necessary, up to a maximum total dose of 5 mg.

Children: 

30 µg/kg of physostigmine by slow intravenous administration.

Repeat after 5 minutes, if necessary up to a maximum total dose of 2 mg.

Fever should be treated symptomatically with tepid sponging or ice packs.

In pronounced restlessness or excitation, diazepam 10 mg may be given by intravenous injection, tachycardia may be treated by intravenous injection of propranolol and urinary retention can be managed by catheterization.

In the event of progression of the curare-like effect to the paralysis of the respiratory muscles, mechanical ventilation will be required.

Pharmacodynamic properties:

Pharmacotherapeutic group: Anticholinergic as well as antispasmodic.

Oxybutynin has both direct antispasmodic action on the smooth muscle of the bladder detrusor muscle as well as an anticholinergic action in blocking the muscarinic effects of acetylcholine on smooth muscle. These properties cause relaxation of the detrusor muscle of the bladder in patients with an unstable bladder. Oxybutynin increases bladder capacity and reduces the incidence of spontaneous contractions of the detrusor muscle.

Pharmacokinetic properties:

Oxybin Tablet:

Oxybutynin is poorly absorbed from the gastrointestinal tract. It is highly bound to plasma proteins; the peak plasma level is reached between 0.5-1 hour after administration. The half-life is biexponential, the first phase being about 40 minutes and the second about 2-3 hours. The elimination half-life may be increased in the elderly, particularly if they are frail.

Oxybutynin and its metabolites are excreted in the feces and urine. There is no evidence of accumulation.

Oxyin Syrup:

Absorption

Oxybutynin is rapidly absorbed from the gastrointestinal tract following oral administration with maximum plasma concentrations reached in less than 1 hour. First-passage effect is high and less than 10% of the administered dose reaches the circulation unchanged.

Distribution

Oxybutynin is widely distributed in body tissues following systemic absorption. The volume of distribution was estimated to be 193 l after intravenous administration of 5 mg oxybutynin hydrochloride.

Metabolism

Oxybutynin is extensively metabolized by the liver¨ primarily by the cytochrome P450 enzyme system¨ particularly CYP 3A4 found mostly in the liver and gut wall. Metabolites include phenylcyclohexylglycolic acid¨ which is pharmacologically inactive¨ and N-desethyloxybutynin¨ which is pharmacologically active.

Excretion

Oxybutynin is extensively metabolized in the liver¨ see above¨ with less than 0.1% of the administered dose excreted unchanged in the urine. Also, less than 0.1% of the administered dose is excreted as the metabolite N-desethyloxybutynin.

Elderly:

Bioavailability is higher in elderly patients; AUC is 2-4-fold higher after repeated administration and half-life 3-5 times longer.

Oxybin Tablet: Store in a dry place, at a temperature not exceeding 30^oC.

Oxybin Syrup: Store at a temperature not exceeding 30^oC.

Oxybin Tablets: Box containing 1, 2 or 100 strips of 10 scored tablets each.

Oxybin Syrup: Box containing a bottle of 120 ml.