28 terms

Anticholinergic Drugs

Anticholinergic drugs
bind to muscarinic receptors and competitively antagonize ACh/ block the ACh receptors
Pharmacologic actions of anticholinergic drugs on resp. system
inhibits secretions and causes bronchodilation
Pharmacologic actions of anitcholinergic drugs on cardiovascular system
increased heart rate/AV conduction
Pharmacologic actions of anticholinergic drugs on GI tract
decrease salivary/GI secretions, decrease motility/antispasmodic action
Pharmacologic actions of anticholinergic drugs on GU
inhibit voiding of urine in over active baldder, contraindicated in males with BPH
Pharmacologic actions of anticholinergic drugs on CNS
sedation especially scopaloamine, cns stimulation/delirium, profound CNS depression and respiratory rate
Pharmacologic actions of anticholinergic drugs on eyes
mydriasis, cyclopegia, dilation of pupils, contraindicated in glaucoma
Atropine: mechanism of action
has a high affinity for muscarinic receptor and competitively binds to prevent ACh from binding to these sites
Atropine: actions on eye
blocks all cholinergic activity resulting in persistant mydriasis and unresponsiveness to light, and cycloplegia
Atropine: contraindication in eye
in patients with narrow angle glaucoma intraocular pressure may rise dangerously
Atropine: actions on GI
used as an antispasmodic to reduce activity of GI tract, but does not affect hydrochloric acid production
Atropine: actions on the Urinary system
reduce hpermotility states of the urinary bladder, and is used in enuresis among children
Atropine: action on cardiovascular
at low doses- decreases cardiac rate due to blockade of M1 receptors
at high doses- M2 receptors on SA node are blocked and cardiac rate increases
at toxic levels will dilate cutaneous vasculature
Atropine: action on secretions
blocks salivary glands, sweat and lacrimal glands are similarly affected
Therapeutic uses of Atropine: eye
permits the measurement of refractive errors without interference by the accommodative capacity of the eye
Therapeutic uses of Atropine: Antispasmodic
used to relax the GI tract and bladder
Therapeutic uses of Atropine: antidote
treatment for overdoses of cholinesterase inhibitor insecticide and some mushroom poisoning also blocks affects of acetylchoinesterase inhibitors like physostigmine
Therapeutic causes for Atropine: antisecretory
block secretions in the upper and lower respiratory tracts prior to surgery
Atropine: pharmacokinetics
atropine is readily absorbed patially metabolized by the liver and eliminatied primarily in the urine
Atropine: adverse effects
drymouth, blurred vision, tachycardia, urinary retention, consitpation, restlessness, confusion, hallucinations, delirium, depression, collapse of the circulatory and respiratory system and death
derivative of atropine that is inhaled because of their positive charges it does not enter the CNS or systemic circulation
Ipratropium: Therapeutic uses
Treats COPD (chronic bronchitis and emphysema) is a bronchodilator
Scopolamine: main clinical uses
intestinal disorders and motion sickness and in obstetrics with morphine to produce amnesia and sedation
Tolterodine: main clinical uses
Used to treat overactive urinary bladder disease; relief of urinary spasms, urgency, and incontinence
Tolterodine: actions
by blocking muscarinic receptors in the bladder, intravesicular pressure is lowered and bladder capacity is increased so the frequency of bladder contraction is reduced
Tolterodine: adverse effects
dry mouth, constipation, blurred vision
Hyoscyamine: main clinical uses
the drug works peripherally, NOT in the CNS. Used for intestinal disorders, diarrhea, irritable bowel syndrome
Toxic effects of atropine and scopolamine
found in many plant berries, can lead to death in a few hours should treat with physiostigmine