Propantheline, 7.5 to 15 mg, may also work well at bedtime or on a tid schedule. Anticholinergic agents, used in the treatment of detrusor hyperactivity, reduce detrusor contractions, an effect that may worsen voiding problems in patients with detrusor hypoactivity or outlet obstruction. Detrusor hyporeflexia, producing incomplete bladder emptying and urinary frequency, may respond to a reduction in the dosage of an anticholinergic antiparkinsonian medication when that is the cause. It is therefore essential that PD patients with urinary dysfunction have urologic evaluations that include recording of bladder and sphincter pressure, sphincter electromyography, and fluoroscopy and that these tests be performed only by a urologist familiar with their interpretation. When cystometric studies reveal a hypoactive detrusor, benefit may be obtained from alpha adrenergic-blocking agents such as phenoxybenzamine or prazosin, which decrease tone in the bladder neck.
Intermittent catheterization is necessary with myogenic overdystension.
Depending on the size of the enlarged prostate, the age and health of the patient, and the extent of obstruction, BPH is treated symptomatically or surgically. Whatever the cause, BPH begins with changes in periurethral glandular tissue. As the prostate enlarges, it may extend into the bladder and obstruct urinary outflow by compressing or distorting the prostatic urethra. BPH may also cause a diverticulum that retains urine when the rest of the bladder empties, possibly leading to calculus formation or cystitis. Clinical features of BPH depend on the extent of prostatic enlargement and the lobes affected.