Medicine: Step 2

Medicine for urge or mixed (stress and urge) incontinence.  Goal is to decrease incontinence episodes by relaxing the detrussor muscle around the bladder.  Side effects of these medicines include

• dry mouth
• blurred vision
• drowsiness
• decreased cognition
• constipation.

Oxybutinin

Mechanism of action:  relaxes the smooth muscle around the bladder causing less urgency and frequency.

Dosage:

• Immediate release: 2.5 – 5mg per 2-3 x a day. Max 30mg/day
• Extended release: 5mg / day/ May 30mg/day
• Transdermal patch (Brand only): 1 patch (3.8mg).  Change twice a week.

Tolterodine (Detrol ®and Detrol LA®):

mechanism of action: antagonism muscarinic receptors thus decreasing detrussor contraction.

dose:

• immediate release: 1-2 mg twice a day
• extended release: 2-4 mg once a day

side effect: may have less dry mouth symptoms than oxybutunin.

Alpha blockers

• tamsulosin (Flomax®) 0.4mg/ day (30 min after meal) max:0.8 mg/day.
• doxazosin (Cardura®) 1mg daily.  May inc to 8mg/day
• terazosin (Hytrin®) 1 mg at bedtime.  May inc to 10-20mg/day

mechanism of action: antagonist or block alpha 1 receptors in the prostate and bladder neck causing relaxation – improves urine flow from overactive bladder secondary to BPH.

side effects:

• postural hypotension
• dizziness
• headache
• weakness
• drowsiness

Notes:

• detrussor hyperactivity with impaired contractility(DHIC) may worsen with muscarinic antagonist?
• may switch to another agent in one becomes ineffective
• wait 4 weeks before titrating the dose.
• menopause may cause atrophic changes in the vaginal area and cause local irritation of the urethral and increase cystitis.  WHI study show increase incontinence with estrogen replacement. 
  So topical estradiol for local symptoms may help with frequency or dysuria and possibly incontinence.
• It is also important to treat constipation with incontinence as bulky stool in intestine may increase pressure on bladder.
• overflow incontinence may occur in women who have a blockage of urinary tract from prolapsed bladder.  Do vaginal exam.
• alpha blockers can be taking with anti cholinergics or anti muscarinics.