Cholinergic antagonist is a general term for agents that bind to cholinoceptors and prevent the effects of acetylcholine and other cholinergic agonists. in this video it explains the types of cholinergic antagonists and their agents ,what are their clinical uses and adverse effects without forgetting their mechanism of actions in the body.
In this video i’m going to talk about cholinergic antagonist also known as anticholinergics this video is part of the series of videos about the autonomic nervous system drugs if you haven’t watched the previous videos i recommend you watch it we are going to cover the types of cholinergic antagonist agents their mechanism of actions clinical uses and lastly
Their side effects cholinergic antagonist also called cholinergic blockers or anticholinergics interrupt parasympathetic nerve impulses in the central nervous system and autonomic nervous system by preventing acetylcholine from stimulating cholinergic receptors there are three groups of cholinergic antagonists which we really need to remember them which are
Anti-muscarinic agents ganglion blockers and neuromuscular blocking agents now let’s go ahead and talk about them anti-muscarinic agents these agents block muscarinic receptors causing inhibition of muscarinic functions in addition these drugs block the few exceptional sympathetic neurons that are cholinergic such as those innervating the salivary and sweat glands
Because they do not block nicotinic receptors the antimuscarinic drugs have little or no action at skeletal neuromuscular junctions or autonomic ganglia a simple mnemonic for you to remember antimuscarinic agents is f g h i o s t where it stands for aquidinium and atropine b stands for benztropine c stands for cyclopentylate d stands for derive feneson f stands
For fisoterodene g stands for glycopyrolate h stands for hyacine i stands for hypertrophium o stands for oxybutynin s stands for scopolamine and solifenesin t stands for tyotropium tolterradine tropicamide trospium and trihexafenidyl now we ask ourselves what are their clinical uses and how are we going to remember the clinical use of each drug since they are
So many it’s frustrating right that’s why we have a simple mnemonic to help you remember the clinical uses of the most of these drugs and that mnemonic is the sentence parkinson was poisoned with anticholinesterase drugs which led to dilation of pupils and irritable bowel syndrome he wanted to treat uncontrolled urination and peptic ulcers doctor asked if he
Had asthma and incontinence or even motion sickness but parkinson didn’t have asthma and incontinence except motion sickness now we got a table here on the left side are the drugs with their brand names and we have letters representing drugs so that it can be easy to remember the names of the drugs b stands for benztropine and a stands for atropine and the list
Goes on what is going to happen is at the right side of the table which have the clinical use we use the mnemonic sentence from the start where benztropine will have parkinson atropine will be with was poisoned with anticholinesterase drugs part of the mnemonic sentence so here means benztropine is used in parkinson’s diseases and atropine is used as antidote in
Anticholinesterase drugs toxicity cyclopentylate is used in dilation of pupils dicyclomine is used in irritable bowel syndrome and dosage form is intramuscular solution oral capsule oral syrup and oral tablet fesoteridine is used in uncontrolled urination dosage form is oral tablet extended release glycopyrolate is used to control conditions such as peptic ulcers
That involve excessive stomach acid production dosage forms are injectable solution intravenous solution oral solution and oral tablet ipratropium guys these drugs ending with em i’m talking about iprotropium and tyotropium.these drugs are bronchodilators that are used to prevent bronchospasm in people with chronic obstructive pulmonary disease and here iprotropium
Is used in people with asthma and the next one is oxybutynine oxybutynin is used in urinary incontinence urinary incontinence is leaking of urine that you can’t control now here is an interesting side of oxibutinin oxibutenin reduces muscle spasms of the bladder and urinary tract that help the body hold urine scopolamine scopolamine is used to prevent nausea and
Vomiting caused by motion sickness trihexaffenidyl trihexafenidyl is used to treat symptoms of parkinson’s disease like stiffness tremors spasms and poor muscle control tyotropium we talked about it as it’s used in asthma tolterridine tultridine is also used in the treatment of urinary incontinence and the last one is mescopolymine methopalamine is used to treat
Peptic ulcers nausea vomiting and motion sickness it reduce stomach acid secretion to help control peptic ulcers although mescopolymine does not help heal an ulcer now let’s see them in details atropine are obtained from a tropo belladonna a toxic perennial herbaceous plant we really need a mnemonic to remember atropine clinical uses which mnemonic is going to
Save us a tropha a stands for antidote for cholinergic agonist and as a midriatic cycloplegic the big key point here is topical atropine exerts both matriarchic and psychoplegic effects and it permits the measurement of refractive errors without interference by the accommodative capacity of the eye t for travelers diarrhea r for rapid onset mushroom poisoning
O for organophosphorous poisoning p for pre-anaesthetic medication n a for arrhythmia by occupying muscarinic receptors atropine blocks the parasympathetic actions of acetylcholine and induces symptoms of the fight-or-flight response most prominent are increased heart rate bronchodilation decreased motility in the gi tract mediasis and decreased secretions from
Glands at therapeutic doses atropine has no effect on nicotinic receptors in ganglia or on skeletal muscle now let us take this question sarin is a nerve gas that is an organophosphate cholinesterase inhibitor which agent could be used as an antidote to sarin poisoning a pilocarpine b carbocal c atropine d physostic mean pause the video and take your time to
Think about this question the correct answer is c since atropine is used as an antidote for cholinergic agonist and sarin is an organophosphate cholinesterase inhibitor i just want you to commit memorize word of tropa don’t forget a tropa guys now for administration of the drugs we need to be alerts first oral and subcutaneous doses are not interchangeable second
Monitor blood pressure pulse and respirations before administration and for at least one hour after subcutaneous administration general actions last about four hours however effects of topical administration in the eye may persist for days and for adverse effects expected adverse effects include dry mouth constipation urinary retention and an increased heart
Rate contraindications atropine is contraindicated in patients with glaucoma because the drug may increase pressure within the eye atropine should not be administered to patients with obstructive disorders of the gastrointestinal tract paralytic ileus bladder neck obstruction benign prostatic hyperplasia myasthenia gravis and cardiac insufficiency and a s for
Atropine toxicity the antidote to atropine is physostigmine or pylocarpine now for iprotropium tiotropium glycopyrolate and aquidinium as we talked before drugs ending with em which are hypertrophium and tiotropium are bronchodilators hypertrophium is classified as a short-acting muscarinic antagonist while glycopyrulate tyotropium and aquidinium are classified
As long-acting muscarinic antagonists based on the duration of action these agents are approved as bronchodilators for maintenance treatment of bronchospasm associated with chronic obstructive pulmonary disease iprotropium and tyotropium are used in the acute management of bronchospasm in asthma and chronic management of asthma respectively all of these agents
Are delivered via inhalation because of the positive charge these drugs do not enter the systemic circulation or the central nervous system scopolamine scopolamine is an oral intravenous ophthalmic or topical drug with many uses including the prevention of motion sickness scopolamine transdermal is used to prevent nausea and vomiting caused by motion sickness or
From anesthesia given during surgery and one thing to note here is you should not use scopolamine transdermal if you have narrow angle glaucoma or if you are allergic to scopolamine now we have another question here which is the most effective drug for motion sickness for a person planning to go on a cruise a atropine b fisoterodene c scopolamine d tropicamide
Pause the video and think guys against copolymine is the most effective in preventing motion sickness so here the answer is again c tropicamide and cyclopentylate these agents are used as ophthalmic solutions for madriasis and cycloplegia their duration of action is shorter than that of atropine tropicamide produces madriasis for six hours and cyclopentylate for
24 hours an overdose of tropicamidophthalmic is not expected to be dangerous so this is normal no need to worry about it benztropine and trihexyfenidyl benztropine and trihexafenidyl are useful as adjuncts with other anti-parkinson agents to treat parkinson disease and other types of parkinsonian syndromes including antipsychotic induced extrapyramidal symptoms
Avoid driving or hazardous activity until you know how benstropine will affect you your reactions could be impaired avoid becoming overheated or dehydrated during exercise and in hot weather ben stropine can decrease sweating and you may be more prone to heat stroke so no driving no staying dehydrated during exercise get emergency help immediately if any of the
Following symptoms of overdose occur while taking benztropine and trihexafenidal blindness blurred vision change in consciousness cold clammy skin decreased vision and dizziness
Transcribed from video
Cholinergic antagonist mnemonics you need to know By Medicine Discovery
