Urinary Incontinence or Retention

Question 1

What is the parasympathetic receptor of the bladder?

Answer 1

M3 receptor

Question 2

What is the neuronal receptor for the external urethral sphincter?

Answer 2

nicotinic receptor

Question 3

Which muscarinic receptor(s) are in the heart? What will blocking them do?

Answer 3

M2. Blockage will cause tachycardia and palpitations

Question 4

Peripheral ADEs of anticholinergic drugs

Answer 4

dry mouth
mydriasis
constipation
urinary retention
tachycardia

Question 5

Central ADEs of anticholinergic drugs

Answer 5

sedation, confusion, hallucinations
slowed cognitive function
sleep disruption

Question 6

Contraindications for anticholinergics?

Answer 6

gluacoma
urinary and gastric obstruction
need for mental alertness
alzheimers/dementia

Question 7

MOA of darifenacin

Answer 7

M3 specific muscarinic acetylcholine receptor blocker to relax bladder smooth muscle

Question 8

ADE of darifenacin

Answer 8

urinary retention
CV effects - LESS tachydacria, prolonged QT
GI - constipation
Contraindicated in glaucoma, urinary obstruction, need for mental alertness and alzheimers.

Question 9

MOA of oxybutynin

Answer 9

nonselective competitive antagonist of M1, M2 and M3 oral immediate release.
Relaxes detrussor.

Question 10

ADE of oxybutynin

Answer 10

urinary retention
CV effects - tachycardia, prolonged QT
dry mouth
GI - constipation
somnolence
Contraindicated in glaucoma, urinary obstruction, need for mental alertness and alzheimers.

Question 11

MOA of solifenacin

Answer 11

nonselective competitive cholinergic receptor antagonist. Prevents muscarinic action thus reduces bladder smooth muscle tone

Question 12

ADE of solifenacin

Answer 12

lesser risk of dry mouth
withdrawel symptoms
urinary retention
CV effects - tachycardia, prolonged QT
GI - constipation
Contraindicated in glaucoma, urinary obstruction, need for mental alertness and alzheimers.

Question 13

MOA of trospium

Answer 13

nonselective muscarinic antagonist, prevents acetylcholine actions on receptor to reduce smooth muscle tone.

Question 14

ADE of trospium

Answer 14

urinary retention
CV effects - tachycardia, prolonged QT
GI - constipation
Contraindicated in glaucoma, urinary obstruction,
*only one good for mental alertness because quartinary

Question 15

MOA of mirabegron

Answer 15

miraBegron = B3 adrenergic agonist; increases bladder capacity by relaxing detrusor smooth muscle.

Question 16

ADE of mirabegron

Answer 16

increases BP

Tachycardia

Question 17

MOA of neostigmine

Answer 17

inhibits acetylcholinesterase, augments action of Ach at both muscarinic and nicotinic receptors to increase smooth muscle tone and cause urination. Used to prevent urinary retention after anesthesia

Question 18

ADE of neostigmine

Answer 18

AV block
bradyarrhythmia
cardiac arrest and dysrhythmia
hypotension
syncope
tachycardia

Question 19

How do sympathomimetics work on urinary system?

Answer 19

act on sympathetic postganglionic neurons to release NE, which activates B3 adrenergic receptors to relax bladder and smooth muscle. Also activates a1 adrenergic receptors to contract urethral smooth muscle.

Question 20

How do opioids cause urinary retention?

Answer 20

they act via mu and delta rectpors to inhibit parasympathetics hence detrussor activation.

Question 21

Which two incontinence drugs are long-acting?

Answer 21

oxybutynin and tolterodine (not on focus list).

Both have short half lives but formulations make them last longer.

Question 22

Which urinary incontinence drug would be least likely to produce somnolence?

Answer 22

trospium

Question 23

Which drug should be given to a patient with abnormally high residual urine volume?

Answer 23

Goal to increase cholinergic tone
Neostigmine = Ach’erase inhibitor
Bethanechol = cholinomimetic agent (treat urinary retention induced by opiods)