Sildenafil

Question 1

What class of drug is sildenafil?

Answer 1

Phosphodiesterase type 5 inhibitor

Question 2

What is the mechanism of action of sildenafil?

Answer 2

Inhibiting phosphodiesterase causes the breakdown of cGMP, which regulates blood to the penis

Question 3

What are the indications for sildenafil?

Answer 3

Erectile dysfunction
Pulmonary arterial hypertension

Question 4

What are the side effects of sildenafil?

Answer 4

Visual disturbances - blue discoloration, non-arteritic anterior ischaemic neuropathy
Nasal congestion
Flushing
GI disturbance
Headache
Priapism

Question 5

What are the contraindications to sildenafil?

Answer 5

Nitrates
Hypotension
Recent stroke or MI

Question 6

What information should patients be given about sildenafil?

Answer 6

Onset of effect may be delayed if taken with food

Question 7

What is the usual dose of sildenafil for erectile dysfunction?

Answer 7

50mg taken approx. 1 hour before sexual activity