Anticholinergics

Question 1

Drugs of the class anticholinergics

Answer 1

Antimuscuranics: ipratropium and tiotropium

Antinicotonics - not need to know

Question 2

Indications of anticholinergics

Answer 2

COPD - short acting are used to releive breathlessness after exercise or in exaceberation of COPD

long acting muscuranics for prevention of breathlessness and exacebrations

Asthma - short acting are added as adjuvant therapy when there is exaceberation

Long acting (LAMA) are added as adjuvant with inhaled coritcosteroid therapy at stage 4, what is the alternative of LAMA

Question 3

when shor tacting muscuranics are added in exacebration of asthma what is it added to?

Answer 3

To short acting beta-2 agonists (salbutamol)

Question 4

What is the alternative of LAMA in stage 4 asthma therapy

Answer 4

it is theophylline

when Px IS >50yrs one considers theophylline or LAMA, otherwise just increase ICS

Question 5

Mechanism of action of Anticholinergics

Answer 5

Antimuscuranics bind to the muscuranic receptor acting as competitive inhibitors of acetycholine

when the muscuranics are blocked the heart rate and conduction is increased

reduce smooth muscle tone even in respiratory tract

reduce secretions in respiratory and GI tracts

Question 6

What happens when muscuranics receptors are stimulated

Answer 6

They have a general parasympathetic “rest and digest” effect

Question 7

Side effects of anticholinergics

Answer 7

When antimuscuranics are inhaled there is very few evidence of side effects other than dry mouth

Question 8

Warnings of anticholinergics

Answer 8

Caution when using in Px of angle closure glaucoma
Caution in Px with arythmias

However in practice it is inhaled and very few problems

Question 9

Interactions of anticholinergics

Answer 9

Very minimal systematic absorption resulting in close o non interactions