Bladder Dysfunction Medication

Medications used in the management of bladder dysfunction include cholinergic agonists, alpha-adrenergic blocking agents, anticholinergic agents, tricyclic antidepressants (TCAs), and sympathomimetic agents.

Class Summary

Cholinergic agents stimulate cholinergic receptors in the smooth muscle of the urinary bladder and gastrointestinal (GI) tract, resulting in increased peristalsis that treats urinary retention resulting from a neurogenic bladder.

Bethanechol hydrochloride (Urecholine)

Bethanechol hydrochloride is used for selective stimulation of the bladder to produce contraction and thereby initiate micturition and empty the bladder. It is most useful in patients who have bladder hypocontractility, provided that they have functional and coordinated sphincters. It is rarely used, because of the difficulty of timing the effect and because of GI stimulation.

Class Summary

Alpha-adrenergic blockers are used to decrease bladder overactivity.

Prazosin (Minipress)

Prazosin improves urine flow rates by relaxing smooth muscle. This relaxation is produced by blocking alpha1 adrenoceptors in the bladder neck and prostate. When increasing dosages, give the first dose of each increment at bedtime to reduce syncopal episodes. Although dosages higher than 20 mg/day usually do not increase efficacy, some patients may benefit from dosages as high as 40 mg/day.

Phenoxybenzamine (Dibenzyline)

Phenoxybenzamine decreases bladder contractions through long-lasting noncompetitive alpha-adrenergic blockade of the postganglionic synapses at the smooth muscle and exocrine glands.

Class Summary

Anticholinergic drugs inhibit the binding of acetylcholine to the cholinergic receptor, thereby suppressing involuntary bladder contraction of any etiology. In addition, they increase the volume of the first involuntary bladder contraction, decrease the amplitude of the involuntary bladder contraction, and may increase bladder capacity.

Propantheline

Propantheline is used for its anticholinergic effect and is given to control symptoms of urinary incontinence secondary to uninhibited bladder contractions related to upper motor neuron lesions.

Oxybutynin (Ditropan XL, Gelnique, Oxytrol)

Oxybutynin is a commonly used drug in patients with bladder disorders and is known for its anticholinergic-antispasmodic effects. It has a smooth muscle–relaxing effect distal to the cholinergic receptor site. It is also available in a long-acting form for once-daily dosing.

Tolterodine tartrate (Detrol, Detrol LA)

Tolterodine tartrate is a competitive muscarinic receptor antagonist for overactive bladder; however, it differs from other anticholinergic types in that it has selectivity for the urinary bladder over the salivary glands. It exhibits a high specificity for muscarinic receptors and has minimal activity or affinity for other neurotransmitter receptors and other potential targets (eg, calcium channels).

Trospium (Sanctura, Sanctura XR)

Trospium is a quaternary ammonium compound that elicits antispasmodic and antimuscarinic effects. It antagonizes the acetylcholine effect on muscarinic receptors. Its parasympathetic effect reduces smooth muscle tone in the bladder. Trospium is indicated for overactive bladder with symptoms of urinary incontinence, urgency, and frequency.

Solifenacin succinate (VESIcare)

Solifenacin succinate elicits competitive muscarinic receptor antagonism, which results in an anticholinergic effect and inhibition of bladder smooth muscle contraction. It is indicated for overactive bladder with symptoms of urgency, frequency, and urge incontinence.

Darifenacin (Enablex)

Darifenacin is an extended-release product that elicits competitive muscarinic receptor antagonism and reduces bladder smooth muscle contractions. It has high affinity for the M3 receptors involved in bladder and GI smooth muscle contraction, saliva production, and iris sphincter function. Darifenacin is indicated for overactive bladder with symptoms of urge incontinence, urgency, and frequency. It should be swallowed whole; it should not be chewed, divided, or crushed.

Fesoterodine (Toviaz)

Fesoterodine is a competitive muscarinic receptor antagonist. Its antagonistic effect results in decreased bladder smooth muscle contractions. Fesoterodine is indicated for symptoms of overactive bladder (eg, urinary urge incontinence, urgency, and frequency). It is available as 4- or 8-mg extended-release tablet.

Class Summary

TCAs have central and peripheral anticholinergic effects, as well as sedative effects, and block the active reuptake of norepinephrine and serotonin. The exact mechanisms by which these drugs act in the treatment of incontinence, however, are not fully understood. The Agency for Health Care Policy and Research (AHCPR) guidelines caution that TCAs should be reserved for use in carefully evaluated patients.

Imipramine hydrochloride (Tofranil, Tofranil-PM)

Imipramine facilitates urine storage by decreasing bladder contractility and increasing outlet resistance. It inhibits reuptake of norepinephrine or serotonin at the presynaptic neuron.

Class Summary

Sympathomimetic drugs increase urethral pressure.

Ephedrine

The use of ephedrine in neurogenic bladder is based on its ability to increase urethral pressure, which would help patients with mild-to-moderate stress incontinence by directly stimulating alpha- and beta-adrenergic receptors.