class 3

Question 1

Name two class 3 anti arrythmic drugs?

Answer 1

1. Amiodorone

2. Sotalol

Question 2

What is the mechanism of action of Amiodorone?

Answer 2

1. Prolongs cardiac action potential by inhibiting K+ channels thus delaying repolarisation
2. Increases refractory period

Question 3

What is Amiodorone used for?

Answer 3

1. Wolf parkinson white syncardiasdrome

2. atrial / ventricular tachy

Question 4

Name 3 factors which limit Amiodone use?

Answer 4

1. Lengthens QT interval - pro arryhmics
2. P450 inhibitor
3. Long half life

Question 5

Name 3 major adverse effects of Amiodorone use

Answer 5

1. Photosensitivity
2. Slate blue - gray discolouration
3. Corneal depositis

Question 6

Name 3 major organs adversely effected by Amiodorone use?

Answer 6

1. Lungs - pulmonary fibrosis
2. Liver - liver fibrosis
3. Thyroid - can cause hyper/hypo thyroidism

Question 7

How much patients on Amiodorone be monitored?

Answer 7

1. TFT, LFT, U&E, CXR prior to treatment

2. TFT, LFT every 6 months

Question 8

What is the mechanism of action of Sotalol?

Answer 8

1. Non selective Beta adrenoreceptor antagonist
2. Delays outward K+ current
3. Prolongs action potential and QT interval