Drugs and Urinary Incontinence

1. Drugs and Urinary Incontinence Cheryl Ritchie R.Ph., CGP Janzen’s Pharmacy Thunder Bay, ON

2. Medications and Urinary incontinencePresentation Outline • Bladder receptors – Drug activity sites • Drugs contributing to urinary incontinence • Drugs for treatment of urinary incontinence

3. Alpha Adrenergic Receptors in Bladder • Stimulation • Sphincter contraction • Inhibit urine flow • Block receptors • Sphincter relaxation • Allow urine flow

4. Beta adrenergic receptors in bladder • Stimulation • Detrusor muscle relaxation • Allows bladder filling • Block receptors • Detrusor muscle contraction • Facilitates bladder emptying

5. Muscarinic (M2 & M3 - Cholinergic) Receptors • Stimulation • Detrusor muscle contraction • Facilitates bladder emptying • Block receptors • Detrusor muscle relaxation • Facilitates bladder filling

6. Medications contributing to Incontinence • Stress Incontinence • Alpha adrenergic blocking agents cause sphincter relaxation • Terazosin • doxazosin • ACE inhibitors may cause cough • Enalapril • Ramipril • Lisinopril • fosinopril

7. Medications contributing to Urinary Incontinence • Urge incontinence due to uncontrolled bladder contractions or increased urine output • Diuretics • Caffeine • Sedative Hypnotics

8. Medications contributing to urinary incontinence • Urinary retention due to decreased bladder contractions • Anticholinergics – oxybutynin, scopolamine • Antidepressants – amitriptyline, doxepin • Antipsychotics – chlorpromazine, prochlorperazine • Sedative hypnotics – diazepam, flurazepam • Antihistamines – diphenhydramine, hydroxyzine, chlorpheniramine • Muscle relaxants – baclofen, cyclobenzaprine • Calcium Channel Blockers – diltiazem,nifedipine, verapamil • Antiarrhytmics - quinidine • Antiparkisonian agents – trihexyphenidyl, benztropine

9. Medications Contributing to Urinary Incontinence • Urinary retention due to sphincter contraction • Alpha adrenergic agonists • pseudoephedrine • Urinary retention due to detrusor muscle relaxation • Beta adrenergic agonists • Salbutamol • terbutaline

10. Medications contributing to urinary incontinence • If medications are a contributing factor – consider an alternative medication • If not able to discontinue offending medication, the lowest possible dose of the aggravating medication should be used.

11. Medications to treat urinary incontinence - goals of treatment • Decrease uninhibited bladder contractions • Increase functional bladder capacity • Decrease frequency and urgency

12. Drugs in the management of urinary incontinence – Points to consider • Will adding medication improve or complicate quality of life? • Drug therapy alone rarely cures elderly urinary incontinence sufferers. • Ensure accurate diagnosis prior to choosing drug therapy

13. Drugs in treatment of urinary incontinence – stress incontinence • Topical estrogens • Increase sphincter tone • Duloxetine – unlabelled use • By blocking norepinehrine reuptake may increase sphincter control

14. Drugs in the treatment of urinary incontinence – Urge incontinence • Oxybutynin - Ditropan • Tolterodine - Detrol

15. Drugs in the treatment of urinary incontinence – Urge incontinence • Adverse effects of oxybutynin & tolterodine • Dry mouth • Constipation • Dry eyes or blurred vision • Tachycardia • Worsening GERD • Worsening cognitive impairment (especially with cholinesterase inhibitors)

16. Drugs in the treatment of urinary incontinence – Urge incontinence • Contraindications • Urinary and gastric retention • Uncontrolled narrow angle glaucoma

17. Drugs in the treatment of urinary incontinence – Urge incontinence • Drug interactions • Additive effects with other anticholinergic medications • Tolterodine only (reduce dose) • Azole antifungals • Cyclosporine • Macrolide antibiotics • Fluoxetine – if possible choose alternative SSRI

18. Drugs in the treatment of urinary incontinence – Urge incontinence • Dosage form availability • Immediate release tablet • Extended release tablet • Transdermal patch (oxybutynin only) • Dosage form notes • Short acting may be good choice for occasional use for special occasions • Long-acting formulation may cause less adverse effects

19. Drugs in the treatment of urinary incontinence – overflow incontinence • UI associated with benign prostatic hyperplasia • Alpha adrenergic antagonists • Terazosin, doxazosin • Non-selective – monitor for hypotension especially with first dose • alfuzocin, tamsulosin • 5-alpha reductase inhibitors • Finasteride, dulasteride

20. Drugs in the management of urinary incontinence – Points to consider • Several weeks of drug therapy are usually required to achieve maximum effect • If no subjective improvement in 4-6 weeks, consider • Increase dose • Change medication • Discontinue medication