anticholinergic drugs (pharmacology) for medical dental and nursing students

ANTICHOLINERGIC DRUGS

Presentation by:Huma Javeriya

Good Morning

Anticholinergic drugs are agents which block the effects of acetylcholine on cholinergic receptors.Also called as Antimuscarinic drugs and Parasympatholytic drugs

CLASSIFICATION

Anticholinergic drugs

Natural alkaloids

Synthetic alkaloids

Mydriatrics

Antispasmotic antisecretory

agents

Antiparkinsonian agents

Semisynthetic alkaloids

NATURAL ALKALIODS Atropine Hyoscine (Scopolamine)

Semisynthetic alkaloidsHomatropineIpratropium bromideTiotropium bromide

Antispasmotic antisecretory agentsPropanthelineDicyclomineOxyphenoniumGlycopyrrolateTelenzepineTolterodinepropiverineAntiparkinsonian agentsBenzhexolbenztropine

MydriaticsEucatropineCyclopentolate tropicamide

Atropine - Prototype

It is obtained from a plant Atropa belladonnaAtropine and scopalamine are belladona alkaloidsThe compete with muscaranic receptors and block themMUSCARANIC ANTAGONISTS

Mechanism of action video

Pharmacokinetics Well absorbed Cross BBB Get metabolised in the liver

Actions

• Stimulates • Restlessness

disorientation hallucinations

• Delirium

• ↓ secretions • Antisialogogue• Sweating is

reduced

• Mydriasis

• GIT and bilary tract : ↓ tone and motility and spasm is relieved

• Bronchodilation• It may cause urinary

retention in people with prostatic hypertrophy.

CVS Secretions

EyeSmooth muscle

USES OF BELLADONNA ALKALOIDS

Antispasmodic •In diarrhoea and dysentery relieves colic & abdominal pain•Renal & bilary colic :Used with morphine to overcomes spasm of sphincter of oddi•Nocturnal enuresis and paraplegia :↓ urinary frequency

Mydriatic &

cycloplegic•Fundoscopic examination of the eye nd error of refraction.•To give rest to the iris

Preanesthetic medication •Reduces salivary and respiratory secretions•Prevents laryngyospasm and brachycardia

Z OPP •Atropine is life saving antidote in case of organophosphorous poisoning and also in mushroom poisoning

Motion sickness •Transdermal hyoscine patches are available that prevent sickness during travelling

During labor •Produces sedation and amnesia

Dose (adults) Repeat

Antisialagogue 0.5 to 1 mg 1-2 hours

Organophosphorus or muscarinic mushroom

poisoning

2 to 3 mg 20-30 minutes

Brady systolic cardiac arrest

1 mg 3-5 minutes; 3 mg maximum total dose

• Fever• Dry mouth• Blurring of vision• Increased blood pressure• Hallucinations.

• Constipation, palpitation, restlessness, convolutions and coma.

• Sundowners syndrome.

Click icon to add picturePhysostigm

ine - Antidote

Atropine substituent's Derivatives used on the eye : Tropicamide over atropine. Antispasmodics and spasmolytics : used to relieve spasms of GIT reduce GI motility.o Peptic ulcer pirenzepine and telenzepineo Bronchial asthma ipratropium over atropine Preanesthetic medication: glycopyrrolate.

Parkinsonism: benztropine and benzhexol Urinary disorders: oxybutinin trospium over

atropine.

Thank you