Chapter 12 & 13 Prototype Drugs

Cholinergic Drugs

bethanechol (Urocholine)

Contraindications

hypersensitivity

mechanical obstruction of the GI or GU tract

Caution ->

history of asthma

ulcer disease

cardiovascular disease

epilepsy

hyperthyroidism

sensitivity to cholinergic agents or effects

Drug-Drug Interactions

Quinidine

Procainamide

cholinesterase inhibitors

ganglionic blocking agents

depolarizing neuromuscular blocking agents

anticholinergics

Adverse Effects

Heart block

syncope

cardiac arrest

bradycardia

hypotension

Mechanism of Action

Stimulate cholinergic receptors

contraction of the bladder

decreased bladder capacity

increased frequency of ureteral peristaltic waves

increased tone and peristalsis in the GI tract

increased pressure in the lower esophageal sphincter

increased gastric secretions

Treatment of Overdose

Atropine sulfate

Side Effects

Headache, malaise

lactimation, miosis

bronchospasm

abdominal discomfort, diarrhea, nausea, salivation, vomiting

urgency

flushing, sweating, hypothermia

Uses

Stimulate bladder emptying

Cholinergic Blocking Drugs

atropine (Atro-Pen)

Drug-Drug Interactions

anything that accentuates the PNSlytic response, ie. procainamide, TCA

Mechanism of Action

antimuscarinic

increase HR

bronchodilates

decreases gastric motility

mydriasis

Uses

antidote for anticholinesterase poisoning

Adverse Effects

dry mouth

constipation

urinary retention

increase HR

CNS excitement leading to delirium

Administration Alerts

monitor BP

monitor pulse

monitor respirations 1 hour before and after

Treatment of Overdose

physostigmine (Antilirium)

Contraindications

glaucoma patients

obstruction patients

BPH

MG

Selective Adrenergic Agonist Drugs

phenylephrine (Neo-synephrine)

Drug-Drug Interactions

MaOi use can result in hypertensive crisis

Administration Alerts

tissue injury (extravasation)

damage to soft contact lenses

Uses

intranasal use/decongestant

dilates pupils

reverse hypotenstion

Contraindications

narrow angle glaucoma patients

heart disease patients

Adverse Effects

hypertension

increased HR leading to severe reflex bradycardia

rebound congestion

narrow angle glaucoma due to secondary mydriatic effect

burning of nasal mucosa

Mechanism of Action

constricts small blood vessels

effects related to fight or flight response

dilates pupils

BLACK BOX WARNING

Death if used IV

Adrenergic Blocking Drugs

prazosin (Minipres)

Mechanism of Action

competes with NE at alpha receptor to block binding

Adverse Effects

orthostatic hypotension

reflex tachycardia

nasal congestion

Uses

decreases BP, no effect on HR

Administration Alerts

short half life, must be given 2-3x/day

start with a low dose to avoid hypotension

Treatment of Overdose

fluid expanders (saline)

vasopressors (dopamine, dobutamine)

Contraindications

caution in elderly patients

caution in those with known allergies to drug

Drug-Drug Interactions

additional anti-hypertensives

diuretics