Riociguat

How it works

It both sensitises soluble guanylate cyclase to endogenous nitric oxide and directly stimulates the enzyme, raising cyclic GMP to produce pulmonary vasodilation.

Prescribing in practice

• Riociguat is contraindicated in pregnancy because it is teratogenic, so pregnancy must be excluded and effective contraception with monthly pregnancy testing maintained in those who can become pregnant.
• It must not be combined with PDE5 inhibitors or nitrates because of the risk of severe hypotension.
• Titrate against blood pressure and symptoms, and use caution in patients prone to hypotension.

Monitoring

Monitor blood pressure during titration, watch for symptomatic hypotension and haemoptysis, and conduct monthly pregnancy testing where applicable.

Counselling the patient

• Do not use this with erectile-dysfunction medicines or any nitrate, and tell other prescribers you take it.
• Effective contraception is essential and you will need regular pregnancy tests.
• Report dizziness, fainting or coughing up blood.

Evidence & guidelines

NICE and trial evidence support riociguat for pulmonary arterial hypertension and inoperable or persistent chronic thromboembolic pulmonary hypertension.