Pharmacology Exam #1: cholinergic agonists

direct acting cholinergic agonists

• mimic effects of ACh binding

• longer DOA than ACh

• little specificity = diffuse effects

Acetylcholine

• SLUDGEBAM

• decrease HR

• decrease CO

• diffuse effects

Bethanechol

• M1 + M3

• DOA: 1 hour

• relaxes bladder

• increases GI motility

Carbachol

• M1 + M2

• N activity → epi from adrenal medulla

• miosis (pupil constriction)

Cevimeline

• M1

• stimulates salivation

• dry mouth tx Sjogren’s

Methacholine

• M

• asthma dx (bronchoconstriction)

Nicotine

• N

• [low] = receptor stimulation

• [high] blocks receptor

Pilocarpine

• M

• xerostomia, glaucoma tx, dry mouth Sjogren’s

• AE = blurred vision + night blindness

indirect acting cholinergic agonists (irreversible)

• inhibits AChE (permanent)

• organophosphates that covalently bind to AChE = increases ACh

• extremely toxic, military nerve agents

Echothiopate

• MOA: irreversibly binds to AChE

• glaucoma tx, can cause cataracts

• DOA: 1-2 weeks

Pralidoxime

• reactivation of AChE

• AChE inhibitor antidote

• does NOT penetrate BBB → unhelpful for use against organophosphates

Atropine

• reactivation of AChE

• competitive at M receptors

• increases CO

• dries secretions

Diazepam

• reactivation of AChE

• decreases convulsions

indirect acting cholinergic agonists (reversible)

• downregulate AChE (prevent degradation)

• affect N, M, + NMJ due to increase in ACh

Donepezil

• Alzheimer’s tx

• GI side effects

• “Donna”

Rivastigmine

• Alzheimer’s tx

• GI side effects

• “Really”

Galantamine

• Alzheimer’s tx

• GI side effects

• “Geriatric”

Edrophonium

• Myasthenia Gravis diagnosis

• DOA: 10-20 minutes

Neostigmine

• Myasthenia Gravis management

• DOA 30 min-2 hours

Pyridostigmine

• Myasthenia Gravis chronic management

• DOA: 3-6 hours

Phyostigmine

• increased M3/M1

• atropine OD

• TCAs

• DOA: 30 min-2 hours

M1

• CNS

• gastric

M2

• heart

• smooth muscle

M3

bladder

“SLUDGEBAM”

Salivation

“SLUDGEBAM”

Lacrimation

“SLUDGEBAM”

Urination

“SLUDGEBAM”

Diarrhea

“SLUDGEBAM”

GI upset

“SLUDGEBAM”

Emesis

“SLUDGEBAM”

Bradycardia

“SLUDGEBAM”

Abdominal cramping

“SLUDGEBAM”

Miosis