Nitrites

Question 1

Name the generic and brand names of nitrites

Answer 1

• Isosorbide mononitrate (Chemydur) – long acting

* Glyceryl trinitrate (Glytrin) – short acting

Question 2

Explain the method of action of nitrites

Answer 2

• Nitrates converted to NO
• NO increases cGMP (cyclic guanosine monophosphate) synthesis = ↓ Ca2+ = muscle relaxation/vasodilation
• Reduction in cardiac work

Question 3

What are the indications for nitrates?

Answer 3

• Treatment of acute angina (glyceryl trinitrate)
• Chest pain associated with coronary syndrome (glyceryl trinitrate)
• Prophylaxis of angina – B blockers/Ca channel blockers are insufficient (isosorbide mononitrate)
• IV used for the treatment of pulmonary oedema

Question 4

What are the contraindications of nitrates?

Answer 4

• Severe aortic stenosis
• Heamodynamic instability
• Hypotension

Question 5

What are the side effects of nitrates?

Answer 5

• Flushing
• Headaches
• Hypotension
• Tolerance = increased symptoms after time

Question 6

What are the interactions with nitrates?

Answer 6

• Phosphodiesterase inhibitor e.g. sidenafil – prolongs hypotensive effect
• Other antihypertensive medication – increases hypotension

Question 7

Which organ eliminates nitrites?

Answer 7

Kidney

Question 8

What patient information would you give to a patient taking nitrites?

Answer 8

• Use sublingual GTN before tasks that bring on angina

* Sit down and rest before and for 5 mins after taken sublingual GTN