Oxybutynin (brand name Ditropan , Lyrinel XL , Lenditro (ZA) , < Driptane (RU) Uripan (Middle East)) is an anticholinergic drug used to relieve bladder and bladder difficulties, including frequent urination and an inability to control urge incontinence, by reducing bladder muscle spasms. It is also given to help the symptoms associated with kidney stones.
This competitive antagonizes M 1 , M 2 , and M 3 subtypes of acetylcholine muscarinic receptor. It also has a direct spasmolytic effect on bladder smooth muscle as a voltage-gated calcium channel antagonist and local anesthetic, but at concentrations far above that used clinically.
Oxybutynin is also a hyperhidrosis treatment (hyperactivity).
Video Oxybutynin
Chemistry
Oxybutynin contains one stereocenter. Commercial formulations are sold as racemates. The ( R ) - enantiomers are stronger anticholinergics than racemates or ( S ) - enantiomers, which are essentially no anticholinergic activity at the doses used in clinical practice. However, ( R ) - self-administered oxybutynin offers little or no clinical benefit above and beyond the racemic mixture. Other measures (calcium antagonism, local anesthesia) oxybutynin are not stereospecific. ( S ) - Oxybutynin has not been clinically tested for its spasmolytic effects, but may be clinically useful for the same indications as racemates, with no unpleasant anticholinergic side effects.
Maps Oxybutynin
Clinical efficacy
In two trials of patients with overactive bladder, 3.9 mg/day of transdermal oxybutynin decreased the incontinence episode and increased mean wrinkle volume to a much greater degree than placebo. There was no difference between the transdermal and the oral tolterodin that were removed for longer.
Adverse effects
Common side effects associated with oxybutynin and other anticholinergics include: dry mouth, difficulty with urination, constipation, blurred vision, drowsiness, and dizziness. Anticholinergics are also known to cause delirium.
It's associated with doses and sometimes heavy. In one population studied - after six months, more than half of patients stopped taking the drug because of side effects and calcium defects. A calcium intake of 800 to 1000 mg is recommended. Dry mouth can be very severe; one estimate is that more than a quarter of patients who start oxybutynin treatment may have to stop because the mouth is dry. The tendency of Oxybutynin to reduce perspiration can be dangerous. The reduced sweating increases the risk of heat exhaustion and heat stroke in a seemingly safe situation where normal sweating makes others feel safe and comfortable. Side effects of increased body temperature are more likely to occur in the elderly and for those with health problems, especially multiple sclerosis.
N -Desethyloxybutynin is an oxybutynin active metabolite that is considered responsible for many of the adverse effects associated with the use of oxybutynin. N -Desethyloxybutynin plasma level can reach as much as six times that of the parent drug after oral release of the formulation immediately. Alternative dosage forms have been developed in an attempt to reduce blood levels of N -desethyloxybutynin and achieve a more stable oxybutynin concentration than is possible with the immediate release form. The long-acting formulation also allows the administration of once-daily and not twice-daily doses required by the immediate release form. The transdermal patch, in addition to the benefits of an extended-release oral formulation, passes a first-pass liver effect that the oral formulation is subjected to. In those with overflow incontinence due to diabetes or neurological diseases such as multiple sclerosis or spinal cord trauma, oxybutin may worsen overflow incontinence because the underlying problem is that the bladder does not contract.
A large study linked the progression of Alzheimer's disease and other forms of dementia to those aged over 65 years to the use of oxybutynin, due to its anticholinergic properties.
Clinical pharmacology
Oxybutynin chloride provides a direct antispasmodic effect on smooth muscle and inhibits muscarinic action of acetylcholine in smooth muscle. This shows one-fifth of anticholinergic activity of atropine in the detrusor muscle of the rabbit, but four to ten times the antispasmodic activity. There are no blocking effects that occur in the skeletal neuromuscular junctions or the autonomic ganglia (antinicotinic effects).
Sources say the drug is absorbed in one hour and has a elimination half-life of 2 to 5 hours. There is wide variation among individuals in blood drug concentrations. This, and low concentrations in urine, indicates that it is removed through the liver.
Contraindications
Oxybutynin chloride is contraindicated in patients with untreated narrow-angle glaucoma, and in patients with untreated anterior chamber angle - since anticholinergic drugs may aggravate this condition. It is also contraindicated in partial or complete obstruction of the gastrointestinal tract, hiatus hernia, gastroesophageal reflux disease, paralytic ileus, elderly bowel imbalance or weak patients, megacolon, toxic megacolon that complicates ulcerative colitis, severe colitis, and myasthenia gravis. It is contraindicated in patients with obstructive uropathy and in patients with unstable cardiovascular status in acute bleeding. Oxybutynin chloride is contraindicated in patients who show hypersensitivity to the product.
Formulation
These are available orally in generic formulations or as brand names Ditropan, Lyrinel XL, or Ditrospam, as transdermal patches under the Oxytrol brand name, and as a topical gel under the Gelnique brand name.
References
External links
- https://web.archive.org/web/20090207085759/http://health.yahoo.com/urinary-medications/oxybutynin-oral/healthwise--d00328a1.html
- http://www.mayoclinic.com/health/drug-information/DR601047
- http://www.medicinenet.com/oxybutynin_er-oral/article.htm
Source of the article : Wikipedia
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