GTN

Question 1

Presentation

Answer 1

1. 300mcg tablet
2. 600mcg tablet
3. 50mg 0.4 mg/hr patch

Question 2

Indications

Answer 2

1. Chest pain in ACS
2. HTN in ACS
3. Autonomic dysreflexia
4. Preterm labour
5. LVHF

Question 3

Contraindications

Answer 3

1. Patch SBP <90
2. Tablet SBP <110
3. Viagra or Levitra within last 24 hrs or Cialis within last 4 days
4. HR <50
5. HR >150
6. VT
7. Right MI
8. Inferior STEMI
9. Known hypersensitivity

Question 4

Precautions

Answer 4

1. No previous administration
2. Elderly or frail
3. Recent MI
4. Current use of tocolytics

Question 5

Side effects

Answer 5

1. Hypotension
2. Headache
3. Tachycardia
4. Bradycardia
5. Skin flushing

Question 6

Pharmacology

Answer 6

GTN is a vascular smooth muscle relaxant and is converted into NO in the body where it….
This causes dephosphorylation of the myosin light chain. Venous dilation which promotes venous pooling and reduces preload and arterial dilation which reduces systemic vascular resistance and arterial pressure, decreasing after load. The above results in reduced myocardial O2 demand, reduced SBP and DBP, mild collateral coronary artery dilation and mild tachycardia. I’m preterm labour GTN causes uterine quiesence.

Question 7

S/L effects

Answer 7

Onset - 30secs to 2mins
Peak - 5-10mins
Duration - 15-30mins

Question 8

IV effects

Answer 8

Onset - 30secs to 1min
Peak - 3-5mins
Duration - 15-30mins

Question 9

Patch effects

Answer 9

Onset - up to 30 mins

Peak - 2hrs

Question 10

Metabolism

Answer 10

Metabolised by the liver