29 terms

MCPA2013-Pharm-Ch 8

Motion Sickness Drugs
*Unknown mechanism in CNS
*Reduces vertigo, post-operative nausea
*Clinical: Prevention of motion sickness & post-operative nausea & vomiting
*Transdermal patch used for motion sickness
*IM injection for postoperative use
*Toxicity: Tachycardia, blurred vision, xerostomia, delirium
*Interactions: With other antimuscarinics
GI disorders
*Competitive antagonist at M3 receptors
*reduces smooth muscle & secretory activity of gut
*Clinical: irritable bowel syndrome, minor diarrhea
*Available in oral and parenteral forms
*Short half-life but action lasts up to 6 hours
*Toxicity: Tachycardia, confusion, urinary retention, increased intraocular pressure
*Interactions: With other antimuscarinics
*Competitive antagonism at all M receptors
*Causes mydriasis (abnormal prolonged pupil dilation) and cycloplegia (paralysis of ciliary muscles of eye)
*Clinical: Retinal examination; prevention of synechiae (eye disease where iris adheres to cornea) after surgery
*Used as drops
*Long action (5-6 days)
*Toxicity: Increased intraocular pressure in closed-angle glaucoma
*Interactions: With other antimuscarinics
Respiratory (Asthma, COPD)
*Competitive, nonselective antagonist at M receptors
*Reduces or prevents bronchospasm
*Clinical: Prevention & relief of acute episodes of bronchospasm
*Aerosol canister, up to qid
*Toxicity: Xerostomia, cough
*Interactions: With other antimuscarinics
*Nonselective muscarinic antagonist
*Reduces detrusor smooth muscle tone, spasms
*Clinical: Urge incontinence; post operative spasms
*Oral, IV, patch formulations
*Toxicity: Tachycardia, constipation, increased intraocular pressure, xerostomia
*Patch: pruritus
*Interactions: With other anti-muscarinics
Cholinergic Poisoning
*Nonselective competitive antagonist @ all muscarinic receptors in CNS & periphery
*Blocks muscarinic excess @ exocrine glands, heart, smooth muscle
*Clinical: mandatory antidote for severe cholinesterase inhibitor poisoning
*IV infusion until anti-muscarinic signs appear
*continue as long as necessary
*Toxicity: Insignificant as long as AChE inhibition continues
Cholinergic Poisoning (2)
*Very high affinity for phosphorus atom but does not enter CNS
*Regenerates active AChE; can relieve skeletal muscle end plate block
*Usual antidote for early-stage (48h) cholinesterase inhibitor poisoning
*IV every 4-6 hours
*Toxicity: Can cause muscle weakness in overdose
atropine and levodopa
What combination of drugs reduces Parkinson induced tremors?
Tropicamide; Homeotropine
_____ and _____ are effective antimuscarinic drugs for use during eye examinations.
Muscarinic receptor blocking drug used to treat asthma
Muscarinic receptor blocking drug used to treat COPD
suppresses; atropine fever
Atropine _____ thermoregulatory sweating possibly leading to _____.
Oxybutine and Trospiumcan
Cholioreceptor blocking drugs that treat bladder spasm after urologic surgery or due to neurologic disorders.
Tolterodine, Fesoterodine, and Imipramine
Cholinoreceptor blocking drugs that can treat incontinence and urolithiasis(urethral stones)
One of the oldest known treatments for motion sickness
_____ can be used to treat pain associated with vasovagal attack during an MI
Darifenacin and Solifenacin
Drugs that have recently been approved for use in the treatment of urinary disorders due to their greater selectivity.
Large doses of _____ are used to treat overdoses of organophosphates and cholinesterase inhibitors.
_____ is a compound used to regenerate active cholinesterase.
Drug Ineffective against organophosphates because it cannot enter the CNS. It works peripherally only and therefore must be given with atropine.
"Dry as a bone, blind as a bat, red as a beet, mad as a hatter and hot as a hater" describes _____.
prostatic hyperplasia
Muscarinic receptor-blocking drugs should be used with caution in elderly men, especially with a history of ____.
At higher concentrations, atropine can block _____ function.
Ganglion-blocking drugs
1) Tetraethylammonium(TEA)
2) Hexamethonium
3) Mecamylamine
4) Trimethaphan
Ganglion-blocking drug with a short duration of action
Ganglion-blocking drug formerly used as drug of choice for hypertension
Ganglion-blocking drug absorbed better in the gut and used for possible treatment for smoking cessation; only ganglion-blocking drug to cross the blood/brain barrier and enter the CNS
Ganglion-blocking drug that is inactive orally and must be given IV; can be used in treatment of hypertensive emergencies and dissecting aortic aneurysm
The blockade effect of ganglion-blocking drugs can be surmounted by increasing the amount of _____.